朱永陵先生にありがとう VAMP2 phluorin を提供するため、シナプトフィジン pHluorin2x 構造と博士ジェームズ e. ロスマンを提供します。彼らのテクニカル サポートおよびヘルプ、博士スーザン ・ チェンと組織プラスミノーゲンアクテベータ電子顕微鏡施設のバージニア クロッカーに感謝します。この作品は国立研究所の神経疾患と脳卒中学内研究プログラム米国の生命研究イニシアティブ プログラム (韓国生物医学科学者フェローシップ プログラム)、韓国研究所からの助成金によって支持されました。バイオ サイエンスとバイオ テクノロジー、大韓民国。

注: 次のプロトコルは、pHluorin イメージング法と培養海馬ニューロン pHluorin モニター シナプス小胞タンパク質吸収細胞内で使用されている EM 方法を説明しますと、EM はシナプス小胞の取り込みを検出し、。微細構造変化します。
 動物のケアとプロシージャの NIH ガイドラインに従った NIH 動物ケアおよび使用委員会によって承認されました。
 1 です。 pHluorin イメージング <ol><li>海馬ニューロンの文化 <ol><li>4 mM NaHCO 3 と 5 mM HEPES を組み合わせることによって準備海馬バッファー (HB) 5 M NaOH で pH 7.3 に調整。Neurobasal、中 2 %b27、0.5 mM L グルタミンと 1% ペニシリン-ストレプトマイシンを混合することによって培養液を作る。さらに、HB バッファーと 20% の混合物を準備ウシ胎児血清 (FBS HB/20%). 
		注: この養殖のプロトコルは、Sankaranarayanan、ら に基づいてください。 29 日 呉 、ら 24</li> <li>培養液に 2 日目に生後 0 日間マウスの子犬の首をはねるし、4 ° C HB/20% FBS に脳を抽出します。脳幹、視床、なったを公開するを削除します。脳幹と視床の除去によってそれを公開した後、なったを分析し、新鮮な 4 ° C HB/20% FBS に転送します 。
		注: 通常、利回りは約 4 x 10 5 セル/mL 1 匹の子犬 (2 つなった) のです。ピンセットやはさみを使用して付着膜をきれいにし、新鮮な 4 ° C HB/20% FBS に転送します。海馬歯状回を引っ張り出すと、はさみで切断することによって、subiculum を分離し、新鮮な 4 ° C HB/20% FBS に転送します</li>。
		<li>約 10 スライスに端から端までを切断することによって各海馬を分割し、15 mL のポリプロピレンの円錐管にそれらを転送します</li>。
		<li>を解決する組織を可能にした後 HB/20% FBS の 10 mL で洗浄し、HB の 10 mL で 3 回洗う</li>。
		<li>は 137 mM の NaCl、KCl 5 mM、7 mM Na2HPO 4 25 mM HEPES、消化ソリューションを準備し、5 M NaOH で pH 7.2 に調整します。なったから上澄みを削除します。トリプシンの 10 mg と 1 mg DNase の消化液 2 mL を加えるし、サンプル ペレットに直接滅菌 0.22 μ m 膜を介してフィルターします</li>。
		<li>なった 37 ° C で 5 分間インキュベートし、HB/20% FBS の 10 mL で 2 回洗浄し、HB の 10 mL で 1 回洗浄.</li>
		<li>解離 MgSO 4 mg を 6 セル &#8729; 7 H 2 O と DNase の 1 mg 2 mL HB と、なった上に滅菌フィルター滅菌 0.22 μ m のフィルターを通してペレットします。軽く気泡を導入することを避けるために世話をしながらの慎重な triturating によって細胞を切り離します。2 分のために解決する組織微粒子を許可し、別のチューブに上清をゆっくり転送します</li>。
		<li>追加 3 mL HB/20% FBS に細胞懸濁液、および遠心分離、または 1,000 rpm、4 ° C で 10 分。上澄みを廃棄し、培地の再懸濁します</li>。
		<li>プレート 60,000 セル、coverslip オフ流出なしのポリ-D-リジン コーティングされた直径 25 mm coverslip の 150 μ L の培地の中断します。めっき後に予め温めておいた培 2 h の 2 mL を追加します。Coverslips 6 ウェル培養プレートまたは滅菌シャーレに保持されます</li>。
		<li>37 ° c 5% で維持する細胞の CO 2 は、14-21 日録音前の培地のインキュベーターを加湿しました。培地の上半分を週に 2 回変更文化成長中です</li>。
	</ol></li> <li>トランスフェクション <ol><li>メッキ後、6-7 日 transfect シナプトフィジン pHluorin 2 X (SpH) または海馬ニューロンに VAMP2 pHluorin。SpH、サイトメガロ ウイルス (CMV) のプロモーターは、pcDNA3 ベクトル 30 に挿入を使用します。VAMP2-pHluorin を使用して pCI ベクトル 31 挿入 CMV プロモーター</li>。
		<li>は、1 μ g のプラスミドを用いた標的細胞に脂質キャリアを使用していずれかのベクトルを transfect します。Transfection のため血清を欠いている、プロトコル手順 1.1.1 から培を使用します。毒性を軽減するトランスフェクション後中 2 h を変更します 。
		注: ボタンで、SpH の低式の場合細胞が健康でない限り、DNA 濃度を脂質キャリアと 2 μ g または培養時間を増加します。通常、4-10 セル (0.006 0.008%) 神経細胞のトランスフェクションした</li>。
	</ol></li> <li>光顕微鏡 <ol><li>119 mM 2 mM の CaCl 2、2.5 mM KCl、25 mM HEPES (pH 7.4) 30 mM グルコース 2 mM MgCl 2、0.01 mM 6-cyano-7-nitroquinoxaline-2,3-dione (塩化ナトリウムから成る生理食塩水の準備CNQX) は、0.05 mM DL-2-アミノ-5-phosphonovaleric 酸 (AP5)。刺激、潤滑剤、シール剤を使用してリークを回避することができるイメージング室培養培地プレートと場所から観察を取る。ガラス、カバーガラスのプレートから商工会議所への転送中にすぐに食塩通常 750 μ L を追加して乾燥させない 。
		注: CNQX と AP5 再発活動の可能性のあるシナプスの活動をブロックするために使用されました。配置する前に倒立蛍光顕微鏡の商工会議所は商工会議所が漏れていないことを確認するのに洗浄ティッシュを使用します。屈折率の変化の結果通常生理食塩水および水浸オイルの混合によって記録中にフォーカスの変更を引き起こす遅い漏れ</li>。
		<li>メタルハライド ランプとレンズの刺激と <ol><li>画像 60 X で広視野倒立顕微鏡上 (1.4 開口) オイルの液浸を記録します。480 の励起ピーク設定フィルター pHluorin を視覚化するフリップ マニュアル 500 550 nm 発光フィルター、490 nm ロングパス鏡 nm。電子乗算電荷結合デバイス (EMCCD) カメラを使用して 2 x 2 のビニングと 100 ms 毎の画像をキャプチャします 。
			注: いくつかの機能は、退色、画像キャプチャ間隔を含むを避けるために適切な条件を達成してフィルター処理に考慮すべき、ビニング、機器に依存しています。共焦点レーザー顕微鏡の場合、レーザー パワーと暴露時間退色を避けるために見なす必要があります。刺激がなければ、少なくとも 3 分を記録した後セットアップを決定し、少なくとも 10 の記録を行った退色をチェックするための刺激がなければ s.</li>
			<li>は、各実験の研究分析の容易さのための高密度エリアを選択します。ブートン、ボタン間の連続式の円形または楕円形の表現パターンに重点を置いて、緑の蛍光性信号によって transfected セルを識別します</li>。
			<li>を使用して 1 刺激による誘発エンドサイトーシス ms パルス、20 mA 活動電位 (AP) パルス刺激装置から供給および白金電極刺激・ アイソレーション ・ ユニット内で配信。刺激と細胞回復中にわたって蛍光活性をイメージします 。
			注: 死んでいるセルの場合式生活研究より強かったし、ボタン間斑点状のパターンを示した</li>。
		</ol></li></ol></li> <li>画像解析 <ol><li>単一のブートンで蛍光強度を分析するため設定を地域の関心 (ROI) 1.5 倍の 1.5 μ m 正方形;ブートンのサイズは約 1.5 μ m 使用退色を確認し、背景として減算への刺激の前にトレース内です</li>。
		<li>正規化蛍光式 (ΔF) を変更: <img alt="Equation"height="11"src="/files/ftp_upload/55862/55862eq1.jpg"width="172"/> 、F 最大 F 0 を参照してください最大増加刺激後・ ベースライン蛍光、それぞれ。として測定するエンドサイトーシス速度減衰率最初 4-10 s pHluorin 蛍光の最大のポイントの後。エンドサイトーシスの継手ベースライン モノラル指数関数にするピーク増加から pHluorin 蛍光減衰時定数 (τ) を取得します</li>。
	</ol></li></ol> 2。電子顕微鏡 <ol><li>準備ポリ-D-リジン コーティング 6 ウェル プレート、常温で 1 h の各ウェルに 0.01% 無菌ろ過ポリ-D-リジン溶液 1.5 mL を適用し、滅菌水で 3 回を洗浄します。分析、文化、1.1.1、1.1.2、1.1.3 の手順のように海馬ニューロンをそれぞれ保持します</li>。
	<li>準備 31.5 mM の NaCl、2 mM CaCl 2、90 mM KCl、25 mM HEPES (pH 7.4) 30 mM グルコースとして HRP に高 K + 刺激ソリューション pH 5 m 7.4 に調整する 2 mM MgCl 2、CNQX 0.01 mM、0.05 mM AP5、5 mg/mL HRP、NaOH。
	<ol><li>1.5 ml の高い海馬ニューロンの文化を刺激するため K + 刺激ソリューション室温 (呼ばれる K +) 各ウェルに 1.5 mL の添加により 90 で s。90 の HRP を 5 mg/mL の同じ濃度を適用 (R と呼ばれる) 静止状態で s、生理食塩水で。回収サンプルの K + サンプル高 K + 刺激ソリューションを適用し、急速に洗って食塩に置き換えるし、10 分間インキュベート</li>
	</ol></li> <li>固定および汚損 <ol><li>pH 7.4 で 21.4 グラム/L の Na cacodylate を使用して 0.1 M Na cacodylate バッファーを準備します。室温で少なくとも 1 時間 0.1 M Na cacodylate バッファーの 4% グルタルアルデヒドでセルを修復します。7 分の 0.1 M Na cacodylate バッファーで 3 回洗って</li>。
		<li>準備ジアミノベンジジン (軽打) ソリューションでは、0.5 mg/mL から成る軽く H 2 O 2 ddH 2 O、0.22 μ m フィルターでフィルターで 0.3%。3 回 7 分の 0.1 M Na cacodylate バッファーを 37 ° c. の洗浄で 30 分の 1.5 mL DAB ソリューションを適用します 。
		注意: DAB は有害と疑われる発がん性物質です。手袋、白衣を使用してください 。
		注: 軽打とラベリング H 2 O 2、その酸化による HRP により触媒とに発生します。サンプルでは、増加する信号のコンポーネントの結果に小さな増加。HRP の濃度を増加させる、触媒の効果がスピードアップします。H 2 O 2 の十分に大きい濃度 32 をラベリングの効果を阻害すると HRP、副反応を衰弱させるを可能にします。今回、このラベリング システムの濃度は現在利用可能な研究 33 , 34 に基づいて選ばれた</li>。
		<li>では、0.1 M Na cacodylate 緩衝固定の記事、4 ° C で 1 時間に 1% OsO 4 の 1.5 mL でニューロンを孵化させなさい。7 分の 0.1 M Na cacodylate バッファーの 1.5 mL で 3 回洗って 。
		注意: 毒性と OsO 4 の反応性のため氷のサンプルをおいて化学フードは孵化に冷蔵庫を使用する多くの場合望ましい</li>。
		<li>準備 0.1 M 酢酸緩衝液 13.61 グラム/L のナトリウム酢酸と 11.43 mL/L 氷酢酸で ph 5.0。1.5 mL の 0.1 M 酢酸緩衝液 pH 5.0 7 分間で 3 回洗浄し、pH 5.0 4 で 1 時間で 0.1 M 酢酸緩衝液で 1.5 mL 1 %005. incubate ° C. 洗浄 3 回 7 分の 1.5 mL の 0.1 M 酢酸緩衝液と</li>。
	</ol></li> <li>エポキシを埋め込む <ol><li>シングル 1.5 mL 各 7 分、50%、70%、90% のエタノールの洗浄とニューロンの文化を脱水し、3 は発煙のフード 7 分 1.5 mL 100% エタノールの洗浄です</li>。
		<li>ミックス 485 mL/L bisphenol-A-(epichlorhydrin) エポキシ樹脂、160 mL/L ドデセニル無水コハク酸 (性)、340 mL/L メチル-5-ノルボルネン-2, 3-ジカルボン酸 (NMA) と 15 mL/L 2,4,6-トリス (dimethylaminomethyl) フェノール (DMP 30) エポキシを作成するには樹脂です。ミックスが徹底的に、空気の泡を削除する真空下で格納します 。
		注: それは特にそれらが肉眼に目に見えるよりも小さい樹脂に空気の泡を削除する重要なので断面中に樹脂のキャビティを引き起こす可能性が</li>。
		<li>50% エポキシとエタノールを置き換えることによってサンプル樹脂、シェーカーで室温で 30 分間エタノールを 70% エタノール シェーカーで室温で 30 分間のエポキシ樹脂そして潜入</li>。
		<li>スイッチ エポキシ 100% エポキシ樹脂でソリューションを樹脂し、50 ° C 追加新鮮な 100% エポキシで 1 時間孵化と新鮮な 100% エポキシ樹脂の 50 ° C の実行の 2 つの取引所で 10 分間インキュベート樹脂し、50 ° c 夜間、60 ・ #17 でのセキュリティを強化することができます。6;36 h 以上を強化するための C.</li>
	</ol></li> <li>ムーティ ウェル プレートから宝石商の各サンプルを削除 &#39; s ハンドソー。密な濃度は、倒立顕微鏡を使用し、ミクロトームによる区分のための 70 に 80 nm ブロックのセルの関心の領域を選択します。ミクロトーム チャック内カットの領域をマウントし、ミクロトームをロードします。ミクロトームでチャックを置き、エッジ ブロックの表面に平行にダイヤモンド ナイフをマウントします。個々 のグリッドに直接 70 に 80 nm 厚のセクションを収集します</li>。
	<li>は、重量、1% 溶液を水に酢酸ウランを溶解し、個別に重量によって 3% の解決のため水にクエン酸鉛を溶解します。15 分間の 1% 水溶液 005. とし、試料のコントラストを改善するために 5 分間 3% 水溶液鉛クエン酸によるセクションを counterstain</li>。
	<li>EM イメージング <ol><li>電子顕微鏡セクションと 10,000-20, 000 × 3 の主な倍率で CCD のデジタル カメラ画像を記録確認します</li>。
	</ol></li> <li>統計 <ol><li>t を実行-制御と実験サンプル平均と標準誤差測定 (s.e.m.) を比較することによって大きな違いを識別するためにテストします</li>。
	</ol>
	</li>
</ol>

<ol>
	<li>Sankaranarayanan, S., Ryan, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-time+measurements+of+vesicle-SNARE+recycling+in+synapses+of+the+central+nervous+system.">Real-time measurements of vesicle-SNARE recycling in synapses of the central nervous system.</a> Nature cell biol. 2 (4), 197-204 (2000).</li><li>Sun, T., Wu, X. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+calcium/calmodulin-activated+calcineurin+in+rapid+and+slow+endocytosis+at+central+synapses.">The role of calcium/calmodulin-activated calcineurin in rapid and slow endocytosis at central synapses.</a> J Neurosci. 30 (35), 11838-11847 (2010).</li><li>Wu, X. -. S. S., Lee, S. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Actin+Is+Crucial+for+All+Kinetically+Distinguishable+Forms+of+Endocytosis+at+Synapses.">Actin Is Crucial for All Kinetically Distinguishable Forms of Endocytosis at Synapses.</a> Neuron. 92 (5), 1020-1035 (2016).</li><li>Granseth, B., Odermatt, B., Royle, S. J., Lagnado, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clathrin-mediated+endocytosis+is+the+dominant+mechanism+of+vesicle+retrieval+at+hippocampal+synapses.">Clathrin-mediated endocytosis is the dominant mechanism of vesicle retrieval at hippocampal synapses.</a> Neuron. 51 (6), 773-786 (2006).</li><li>Atluri, P. P., Ryan, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+kinetics+of+synaptic+vesicle+reacidification+at+hippocampal+nerve+terminals.">The kinetics of synaptic vesicle reacidification at hippocampal nerve terminals.</a> J Neurosci. 26 (8), 2313-2320 (2006).</li><li>Royle, S. J., Granseth, B., Odermatt, B., Derevier, A., Lagnado, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imaging+phluorin-based+probes+at+hippocampal+synapses.">Imaging phluorin-based probes at hippocampal synapses.</a> Methods Mol Biol. 457, 293-303 (2008).</li><li>Moulder, K. L., Mennerick, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reluctant+vesicles+contribute+to+the+total+readily+releasable+pool+in+glutamatergic+hippocampal+neurons.">Reluctant vesicles contribute to the total readily releasable pool in glutamatergic hippocampal neurons.</a> J Neurosci. 25 (15), 3842-3850 (2005).</li><li>Li, Z., Burrone, J., Tyler, W. J., Hartman, K. N., Albeanu, D. F., Murthy, V. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synaptic+vesicle+recycling+studied+in+transgenic+mice+expressing+synaptopHluorin.">Synaptic vesicle recycling studied in transgenic mice expressing synaptopHluorin.</a> Proc Natl Acad Sci U S A. 102 (17), 6131-6136 (2005).</li><li>Morris, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elements+of+a+neurobiological+theory+of+hippocampal+function:+the+role+of+synaptic+plasticity,+synaptic+tagging+and+schemas.">Elements of a neurobiological theory of hippocampal function: the role of synaptic plasticity, synaptic tagging and schemas.</a> Eur J Neurosci. 23 (11), 2829-2846 (2006).</li><li>Sankaranarayanan, S., Ryan, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium+accelerates+endocytosis+of+vSNAREs+at+hippocampal+synapses.">Calcium accelerates endocytosis of vSNAREs at hippocampal synapses.</a> Nat Neurosci. 4 (2), 129-136 (2001).</li><li>Balaji, J., Armbruster, M., Ryan, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium+control+of+endocytic+capacity+at+a+CNS+synapse.">Calcium control of endocytic capacity at a CNS synapse.</a> J Neurosci. 28 (26), 6742-6749 (2008).</li><li>Ferguson, S. M., Brasnjo, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+selective+activity-dependent+requirement+for+dynamin+1+in+synaptic+vesicle+endocytosis.">A selective activity-dependent requirement for dynamin 1 in synaptic vesicle endocytosis.</a> Science. 316 (5824), 570-574 (2007).</li><li>Baydyuk, M., Wu, X. S., He, L., Wu, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brain-derived+neurotrophic+factor+inhibits+calcium+channel+activation,+exocytosis,+and+endocytosis+at+a+central+nerve+terminal.">Brain-derived neurotrophic factor inhibits calcium channel activation, exocytosis, and endocytosis at a central nerve terminal.</a> J Neurosci. 35 (11), 4676-4682 (2015).</li><li>Wu, X. S., Zhang, Z., Zhao, W. D., Wang, D., Luo, F., Wu, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcineurin+is+universally+involved+in+vesicle+endocytosis+at+neuronal+and+nonneuronal+secretory+cells.">Calcineurin is universally involved in vesicle endocytosis at neuronal and nonneuronal secretory cells.</a> Cell Rep. 7 (4), 982-988 (2014).</li><li>Zhang, Z., Wang, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+SNARE+proteins+SNAP25+and+synaptobrevin+are+involved+in+endocytosis+at+hippocampal+synapses.">The SNARE proteins SNAP25 and synaptobrevin are involved in endocytosis at hippocampal synapses.</a> J Neurosci. 33 (21), 9169-9175 (2013).</li><li>Wu, L. -. G. G., Hamid, E., Shin, W., Chiang, H. -. C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exocytosis+and+endocytosis:+modes,+functions,+and+coupling+mechanisms.">Exocytosis and endocytosis: modes, functions, and coupling mechanisms.</a> Annu Rev Physiol. 76 (1), 301-331 (2014).</li><li>Daniele, F., Di Cairano, E. S., Moretti, S., Piccoli, G., Perego, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TIRFM+and+pH-sensitive+GFP-probes+to+evaluate+neurotransmitter+vesicle+dynamics+in+SH-SY5Y+neuroblastoma+cells:+cell+imaging+and+data+analysis.">TIRFM and pH-sensitive GFP-probes to evaluate neurotransmitter vesicle dynamics in SH-SY5Y neuroblastoma cells: cell imaging and data analysis.</a> J Vis Exp. (95), e52267 (2015).</li><li>Shaner, N. C., Lin, M. Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improving+the+photostability+of+bright+monomeric+orange+and+red+fluorescent+proteins.">Improving the photostability of bright monomeric orange and red fluorescent proteins.</a> Nat Methods. 5 (6), 545-551 (2008).</li><li>Li, Y., Tsien, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=pHTomato,+a+red,+genetically+encoded+indicator+that+enables+multiplex+interrogation+of+synaptic+activity.">pHTomato, a red, genetically encoded indicator that enables multiplex interrogation of synaptic activity.</a> Nat Neurosci. 15 (7), 1047-1053 (2012).</li><li>Leitz, J., Kavalali, E. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fast+retrieval+and+autonomous+regulation+of+single+spontaneously+recycling+synaptic+vesicles.">Fast retrieval and autonomous regulation of single spontaneously recycling synaptic vesicles.</a> Elife. 3, e03658 (2014).</li><li>Bisht, K., El Hajj, H., Savage, J. C., S&#225;nchez, M. G., Tremblay, M. -. &. #. 2. 0. 0. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Correlative+Light+and+Electron+Microscopy+to+Study+Microglial+Interactions+with+&#946;-Amyloid+Plaques.">Correlative Light and Electron Microscopy to Study Microglial Interactions with &#946;-Amyloid Plaques.</a> J Vis Exp. (112), e54060 (2016).</li><li>Schikorski, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+Synaptic+Vesicle+Protein+Sorting+with+Enhanced+Horseradish+Peroxidase+in+the+Electron+Microscope.">Monitoring Synaptic Vesicle Protein Sorting with Enhanced Horseradish Peroxidase in the Electron Microscope.</a> High-Resolution Imaging of Cellular Proteins: Methods and Protocols. , 327-341 (2016).</li><li>Kononenko, N. L., Puchkov, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clathrin/AP-2+mediate+synaptic+vesicle+reformation+from+endosome-like+vacuoles+but+are+not+essential+for+membrane+retrieval+at+central+synapses.">Clathrin/AP-2 mediate synaptic vesicle reformation from endosome-like vacuoles but are not essential for membrane retrieval at central synapses.</a> Neuron. 82 (5), 981-988 (2014).</li><li>Wu, Y., O'Toole, E. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+dynamin+1-,+dynamin+3-+and+clathrin-independent+pathway+of+synaptic+vesicle+recycling+mediated+by+bulk+endocytosis.">A dynamin 1-, dynamin 3- and clathrin-independent pathway of synaptic vesicle recycling mediated by bulk endocytosis.</a> eLife. 2014 (3), e01621 (2014).</li><li>Heuser, J. E., Reese, T. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evidence+for+recycling+of+synaptic+vesicle+membrane+during+transmitter+release+at+the+frog+neuromuscular+junction.">Evidence for recycling of synaptic vesicle membrane during transmitter release at the frog neuromuscular junction.</a> J Cell Biol. 57 (2), 315-344 (1973).</li><li>Ceccarelli, B., Hurlbut, W. P., Mauro, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Turnover+of+transmitter+and+synaptic+vesicles+at+the+frog+neuromuscular+junction.">Turnover of transmitter and synaptic vesicles at the frog neuromuscular junction.</a> J Cell Biol. 57 (2), 499-524 (1973).</li><li>Watanabe, S., Rost, B. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrafast+endocytosis+at+mouse+hippocampal+synapses.">Ultrafast endocytosis at mouse hippocampal synapses.</a> Nature. 504 (7479), 242-247 (2013).</li><li>Watanabe, S., Trimbuch, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clathrin+regenerates+synaptic+vesicles+from+endosomes.">Clathrin regenerates synaptic vesicles from endosomes.</a> Nature. 515 (7526), 228-233 (2014).</li><li>Sankaranarayanan, S., Atluri, P. P., Ryan, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Actin+has+a+molecular+scaffolding,+not+propulsive,+role+in+presynaptic+function.">Actin has a molecular scaffolding, not propulsive, role in presynaptic function.</a> Nat Neurosci. 6 (2), 127-135 (2003).</li><li>Zhu, Y., Xu, J., Heinemann, S. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+pathways+of+synaptic+vesicle+retrieval+revealed+by+single-vesicle+imaging.">Two pathways of synaptic vesicle retrieval revealed by single-vesicle imaging.</a> Neuron. 61 (3), 397-411 (2009).</li><li>Miesenbock, G., De Angelis, D. A., Rothman, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualizing+secretion+and+synaptic+transmission+with+pH-sensitive+green+fluorescent+proteins.">Visualizing secretion and synaptic transmission with pH-sensitive green fluorescent proteins.</a> Nature. 394 (6689), 192-195 (1998).</li><li>Arnao, M. B. B., Acosta, M., del Rio, J. A. A., Garc&#237;a-C&#225;novas, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inactivation+of+peroxidase+by+hydrogen+peroxide+and+its+protection+by+a+reductant+agent.">Inactivation of peroxidase by hydrogen peroxide and its protection by a reductant agent.</a> Biochim Biophys Acta. 1038 (1), 85-89 (1990).</li><li>De&#225;k, F., Schoch, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synaptobrevin+is+essential+for+fast+synaptic-vesicle+endocytosis.">Synaptobrevin is essential for fast synaptic-vesicle endocytosis.</a> Nat Cell Biol. 6 (11), 1102-1108 (2004).</li><li>Clayton, E. L., Evans, G. J. O., Cousin, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bulk+synaptic+vesicle+endocytosis+is+rapidly+triggered+during+strong+stimulation.">Bulk synaptic vesicle endocytosis is rapidly triggered during strong stimulation.</a> J Neurosci. 28 (26), 6627-6632 (2008).</li><li>Kavalali, E. T., Jorgensen, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualizing+presynaptic+function.">Visualizing presynaptic function.</a> Nat Neurosci. 17 (1), 10-16 (2014).</li><li>Wienisch, M., Klingauf, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vesicular+proteins+exocytosed+and+subsequently+retrieved+by+compensatory+endocytosis+are+nonidentical.">Vesicular proteins exocytosed and subsequently retrieved by compensatory endocytosis are nonidentical.</a> Nat Neurosci. 9 (8), 1019-1027 (2006).</li><li>Fern&#225;ndez-Alfonso, T., Kwan, R., Ryan, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synaptic+vesicles+interchange+their+membrane+proteins+with+a+large+surface+reservoir+during+recycling.">Synaptic vesicles interchange their membrane proteins with a large surface reservoir during recycling.</a> Neuron. 51 (2), 179-186 (2006).</li><li>Gimber, N., Tadeus, G., Maritzen, T., Schmoranzer, J., Haucke, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diffusional+spread+and+confinement+of+newly+exocytosed+synaptic+vesicle+proteins.">Diffusional spread and confinement of newly exocytosed synaptic vesicle proteins.</a> Nat Commun. 6, 8392 (2015).</li><li>Nicholson-Fish, J. C., Smillie, K. J., Cousin, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+activity-dependent+bulk+endocytosis+with+the+genetically-encoded+reporter+VAMP4-pHluorin.">Monitoring activity-dependent bulk endocytosis with the genetically-encoded reporter VAMP4-pHluorin.</a> J Neurosci Methods. 266, 1-10 (2016).</li><li>Burrone, J., Li, Z., Murthy, V. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+vesicle+cycling+in+presynaptic+terminals+using+the+genetically+encoded+probe+synaptopHluorin.">Studying vesicle cycling in presynaptic terminals using the genetically encoded probe synaptopHluorin.</a> Nat Protoc. 1 (6), 2970-2978 (2006).</li><li>Wisse, E., Braet, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fixation+methods+for+electron+microscopy+of+human+and+other+liver.">Fixation methods for electron microscopy of human and other liver.</a> World journal of gastroenterology. 16 (23), 2851-2866 (2010).</li><li>Magidson, V., Khodjakov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circumventing+Photodamage+in+Live-Cell+Microscopy.">Circumventing Photodamage in Live-Cell Microscopy.</a> Methods in Cell Biology. 114, 545-560 (2013).</li><li>S&#248;ndergaard, C. R., Garrett, A. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+artifacts+in+protein-ligand+X-ray+structures:+implications+for+the+development+of+docking+scoring+functions.">Structural artifacts in protein-ligand X-ray structures: implications for the development of docking scoring functions.</a> J Med Chem. 52 (18), 5673-5684 (2009).</li></ol>

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ここでは、シナプス小胞エンドサイトーシスを監視するための 2 つの方法を示します。最初のメソッドでは、pHluorin transfected ニューロンのシナプス小胞タンパク質と融合し、その後電気刺激を監視しました。第二に、kcl と HRP 取り込みの EM イメージングを使用しました。2 つの理由のためにさまざまな刺激を使いました。まず、高カリウム施肥は文化のすべてのニューロンの脱分極を誘導し?...

神経伝達物質は、シナプス小胞に格納され、エキソサイトーシスによってリリースされました。シナプス小胞膜および蛋白質は、エンドサイトーシス、によって、開口放出の次のラウンドで再利用します。シナプス小胞エンドサイトーシスは、細胞膜から突き出た小胞を削除しますシナプス小胞のプールを維持するため重要です。酸性情況で急冷、中性 pH で蛍光 pH 敏感な緑色蛍光タンパク質 pHluorin は、エンドサイトーシス時間コース ライブ セル1,2,3を測定する使用されています。PHluorin 蛋白質は通常シナプトフィジンや VAMP2/シナプトブレビンなどのシナプス小胞タンパク質の内腔側に接続されています。でも、pHluorin はシナプス小胞の 5.5 の pH ルーメンで急冷され。細胞膜に小胞の融合を公開、pH が 7.3 〜 細胞外の溶液に小胞の内腔 pHluorin 蛍光性の増加の結果します。エキソサイトーシス後、シナプス小胞蛋白質それら回復小胞内小胞再酸性化に続いてのエンドサイトーシスによる増加の蛍光が崩壊します。崩壊は、エンドサイトーシスと小胞の再酸性化を反映しているが、再酸性化がほとんど条件1,4エンドサイトーシスよりも速いのでそれ主のエンドサイトーシスを反映します。再酸性の時定数は 3-4 秒または 10 よりも一般に高速は5,6に少ない s 以上の小胞エンドサイトーシス4,5に必要な。シナプス小胞タンパク質を取得するかどうかを決定する 5.5 の pH の 4 Morpholineethanesulfonic 酸 (MES) 溶液 (25 mM) を用いた酸焼入れ実験を使用ことができます実験が再酸性からエンドサイトーシスを区別するために必要な場合エンドサイトーシス1,3,4を介して原形質膜。したがって、pHluorin 蛍光強度増加エキソおよびエンドサイトーシス、残高反映して反映されます神経刺激後減少特にエンドサイトーシス。
確率誘発リリースと自発的な解放9および pHluorin イメージングがエンドサイトーシスの時間のコースもシナプス小胞プール7、8サイズを測定するだけではなく使えます。多くの要因とエンドサイトーシスなどカルシウム、水溶性 NSF 添付ファイル蛋白質受容体 (スネア) 蛋白質、脳由来神経栄養 factor(BDNF)、カルシニューリンの調節に関与するタンパク質は、pHluorin イメージング1を使用して識別されています。,2,10,11,12,13,14,15,16. 唯一の第一次ニューロンではなく観察17神経芽細胞腫、さらに、神経伝達物質の放出が検出できます。最近では、pHluorin 亜種、下流、mOrange、pHTomato は、単一シナプス18,19で複数の要因を同時記録を監視するため開発されました。たとえば、pHTomato シナプトフィジンと融合され遺伝的コード化カルシウム インジケーター (GCaMP5K) とシナプス小胞の融合およびシナプス コンパートメント20の Ca2 +流入監視に使用します。そのため、シナプス蛋白質に接続されている pHluorin は、エンドサイトーシスとエキソサイトーシスとの関係を分析する有用な方法を提供します。
EM は一般的エンドサイトーシス中の微細構造の変化を示す高空間分解能のためのエンドサイトーシスを研究するために使用する別の方法です。2 つの一般的な領域は、神経細胞21内の病理学的変化を視覚化し、小胞蛋白質22を追跡する機能です。特に、シナプス小胞の取り込み、膜の曲率の観察 periactive ゾーンにクラスリン被覆し、エンドソーム構造が EM3,23,24,25 で可能 ,26,,2728。EM で定着剤による奇形などの潜在的なアーティファクトは、エンドサイトーシス、影響を与える可能性があります、データ分析は労働集約型、解像度は細胞構造を視覚化するための魅力的な機会を提供します。潜在的な定着性の問題と EM の時間分解能の限界は、凍結、エンドサイトーシス27の間に現在の繊細な構造の安定化の高速で非化学メソッドを提供する高圧で克服できます。

<table>
	<tbody>
		<tr>
			<td>Lipofectamine LTX with Plus</td>
			<td>Thermo Fisher</td>
			<td>15338-100</td>
			<td>Transfection of plasmid DNA including synaptophysin or VAMP2-pHluorin</td>
		</tr>
		<tr>
			<td>neurobasal medium</td>
			<td>Thermo Fisher</td>
			<td>21103-049</td>
			<td>Growth medium for neuron, Warm up to 37&#176;C before use</td>
		</tr>
		<tr>
			<td>B27</td>
			<td>Thermo Fisher</td>
			<td>17504-044</td>
			<td>Gradient for neuronal differentiation</td>
		</tr>
		<tr>
			<td>Glutamax</td>
			<td>Thermo Fisher</td>
			<td>35050-061</td>
			<td>Gradient for neuronal culture</td>
		</tr>
		<tr>
			<td>Poly-D-Lysine coated coverslip</td>
			<td>Neuvitro</td>
			<td>GG-25-pdl</td>
			<td>Substrate for neuronal growth and imaging of pHluorin</td>
		</tr>
		<tr>
			<td>Trypsin XI from bovine pancrease</td>
			<td>Sigma</td>
			<td>T1005</td>
			<td>Neuronal culture-digest hippocampal tissues</td>
		</tr>
		<tr>
			<td>Deoxyribonuclease I from bovine pancreas</td>
			<td>Sigma</td>
			<td>D5025</td>
			<td>Neuronal culture-inhibits viscous cell suspension</td>
		</tr>
		<tr>
			<td>pulse stimulator</td>
			<td>A-M systems</td>
			<td>model 2100</td>
			<td>Apply electrical stimulation</td>
		</tr>
		<tr>
			<td>Slotted bath with field stimulation</td>
			<td>Warner Instruments</td>
			<td>RC-21BRFS</td>
			<td>Apply electrical stimulation</td>
		</tr>
		<tr>
			<td>stimulus isolation unit</td>
			<td>Warner Instruments</td>
			<td>SIU102</td>
			<td>Apply electrical stimulation</td>
		</tr>
		<tr>
			<td>lubricant</td>
			<td>Dow corning</td>
			<td>111</td>
			<td>pHluorin imaging-seal with coverslip and imaging chamber, avoid leak from chamber</td>
		</tr>
		<tr>
			<td>AP5</td>
			<td>Tocris</td>
			<td>3693</td>
			<td>Gradient for normal saline, selective NMDA receptor antagonist, inhibit postsynaptic activity which have potential for recurrent activity</td>
		</tr>
		<tr>
			<td>CNQX</td>
			<td>Tocris</td>
			<td>190</td>
			<td>Gradient for normal saline, competitive AMPA/kainate receptor antagonist, inhibit postsynaptic activity which have potential for recurrent activity</td>
		</tr>
		<tr>
			<td>Illuminator</td>
			<td>Nikon</td>
			<td>C-HGFI</td>
			<td>Metal halide light source for pHluorin</td>
		</tr>
		<tr>
			<td>EMCCD camera</td>
			<td>Andor</td>
			<td>iXon3</td>
			<td>pHluorin imaging, detect pHluorin fluorescence intensity</td>
		</tr>
		<tr>
			<td>Inverted microscopy</td>
			<td>Nikon</td>
			<td>Ti-E</td>
			<td>Imaging for synaptophysin or VAMP2 pHluorin transfected cells</td>
		</tr>
		<tr>
			<td>NIS-Elements AR</td>
			<td>Nikon</td>
			<td>NIS-Elements Advanced Research</td>
			<td>Software for imaging acquisition and analysis</td>
		</tr>
		<tr>
			<td>Igor Pro</td>
			<td>WaveMetrics</td>
			<td>Igor pro</td>
			<td>Software for imaging analysis and data presentation</td>
		</tr>
		<tr>
			<td>imaging chamber</td>
			<td>Warner Instruments</td>
			<td>RC21B</td>
			<td>pHluorin imaging, apply field stimulation on living cells</td>
		</tr>
		<tr>
			<td>poly-l-lysine</td>
			<td>Sigma</td>
			<td>P4832</td>
			<td>Electron microscopy, substrate for neuronal growth, apply on multiwell plate for 1 h at room temperature then wash with sterilized water 3 times</td>
		</tr>
		<tr>
			<td>Horseradish peroxidase(HRP)</td>
			<td>Sigma</td>
			<td>P6782</td>
			<td>Electron microscopy, labeling of endocytosed synaptic vesicles by catalyzing DAB in presence hydrogen peroxide, final concentration is 5 mg/mL in normal saline, make fresh before use</td>
		</tr>
		<tr>
			<td>Na cacodylate</td>
			<td>Electron Microscopy Sciences</td>
			<td>12300</td>
			<td>Electron microscopy, buffer for fixatives and washing, final concentration is 0.1 N</td>
		</tr>
		<tr>
			<td>3,3&#8242;-Diaminobenzidine(DAB)</td>
			<td>Sigma</td>
			<td>D8001</td>
			<td>Electron microscopy, labeling of endocytosed synaptic vesicles, substrate for HRP, final concentration is 0.5 mg/mL in DDW and filtered, make fresh before use</td>
		</tr>
		<tr>
			<td>Hydrogen peroxide solution</td>
			<td>Sigma</td>
			<td>H1009</td>
			<td>Electron microscopy, labeling of endocytosed synaptic vesicles by inducing HRP-DAB reaction, final concentration is 0.3% in DDW, make fresh before use</td>
		</tr>
		<tr>
			<td>glutaraldehyde</td>
			<td>Electron Microscopy Sciences</td>
			<td>16365</td>
			<td>Electron microscopy, fixatives, final concentration is 4% in Na-cacodylate buffer, make fresh before use, shake well before to use</td>
		</tr>
		<tr>
			<td>TEM</td>
			<td>JEOL</td>
			<td>200CX</td>
			<td>Electron microscopy, imaging of endocytosed vesicles and ultrastructural changes</td>
		</tr>
		<tr>
			<td>CCD digital camera</td>
			<td>AMT</td>
			<td>XR-100</td>
			<td>Electron microscopy, capturing images</td>
		</tr>
		<tr>
			<td>Lead citrate</td>
			<td>Leica microsystems</td>
			<td>16707235</td>
			<td>Electron microscopy, grid staining</td>
		</tr>
	</tbody>
</table>

measuring synaptic vesicle endocytosis in cultured hippocampal neurons

エンドサイトーシス、時にシナプス小胞の融合は小胞リサイクルそしてこうして神経反復焼成時におけるシナプス伝達の維持を可能にする神経終末で取得されます。病理学の条件に障害エンドサイトーシスは、シナプスの強さと脳の機能の低下につながります。ここでは、我々 は哺乳類神経培養海馬シナプスにおけるシナプス小胞エンドサイトーシスを測定するために使用方法を説明します。我々 は pHluorin、増加 pH 敏感な緑色蛍光タンパク質を小胞の内腔側でシナプトフィジンと VAMP2/シナプトブレビンを含むシナプス小胞膜タンパク質を融合することでシナプス小胞タンパク質エンドサイトーシスを監視、pH として蛍光強度が増加します。エキソサイトーシス、時小胞内腔 pH が増加し、pH は酸性再エンドサイトーシス小胞内腔中。したがって、pHluorin の蛍光強度の増加は減少を示す標識のシナプス小胞タンパク質のエンドサイトーシスに対し融合を示します。PHluorin イメージング法を使用して、エンドサイトーシスを記録するに加え、膜小胞エンドサイトーシスの監視西洋わさびペルオキシダーゼ (HRP) 摂取量の電子顕微鏡検査 (EM) 測定による小胞によって。最後に、我々 は神経末端の穴を形成する高カリウム誘起脱分極後様々 な時を監視しました。HRP 吸収と膜ピット形成の時間的経過は、エンドサイトーシスの時間コースを示します。

脂質キャリア メソッドを使用して、SpH に表現された海馬ニューロン ボタン (図 1 a) の同定を可能にします。電気刺激誘発細胞エキソサイトーシスと蛍光強度の増加に対応。蛍光 (ΔF) の増加は、刺激 (図 1 b) を終了することによって停止されました。増加の蛍光は、エンドサイトーシスにより、低速の減少が続いた。VAMP2-pH...

Watch this Scientific Journal Video about Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons at JoVE.com

Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons

光顕微鏡によるシナプス小胞タンパク質と融合した 1p-169 と吸収小胞の電子顕微鏡によるシナプス小胞エンドサイトーシスが検出されました。

培養海馬神経細胞のシナプス小胞エンドサイトーシスを測定

During endocytosis, fused synaptic vesicles are retrieved at nerve terminals, allowing for vesicle recycling and thus the maintenance of synaptic ...

measuring-synaptic-vesicle-endocytosis-in-cultured-hippocampal-neurons

Research

JoVE Journal

Neuroscience

9.8K ビュー.  National Institute of Neurological Disorders and Stroke. 光顕微鏡によるシナプス小胞タンパク質と融合した 1p-169 と吸収小胞の電子顕微鏡によるシナプス小胞エンドサイトーシスが検出されました。

ビデオ: Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons

Studying Synaptic Vesicle Pools using Photoconversion of Styryl Dyes

The fusion of synaptic vesicles with the plasma membrane (exocytosis) is a required step in neurotransmitter release and neuronal communication. The vesicles are then retrieved from the plasma membrane (endocytosis) and grouped together with the general pool of vesicles within the nerve terminal, until they undergo a new exo- and endocytosis cycle (vesicle recycling). These processes have been studied using a variety of techniques such as electron microscopy, electrophysiology recordings, amperometry and capacitance measurements. Importantly, during the last two decades a number of fluorescently labeled markers emerged, allowing optical techniques to track vesicles in their recycling dynamics. One of the most commonly used markers is the styryl or FM dye 1; structurally, all FM dyes contain a hydrophilic head and a lipophilic tail connected through an aromatic ring and one or more double bonds (Fig. 1B). A classical FM dye experiment to label a pool of vesicles consists in bathing the preparation (Fig. 1Ai) with the dye during the stimulation of the nerve (electrically or with high K+). This induces vesicle recycling and the subsequent loading of the dye into recently endocytosed vesicles (Fig. 1Ai-iii). After loading the vesicles with dye, a second round of stimulation in a dye-free bath would trigger the FM release through exocytosis (Fig. 1Aiv-v), process that can be followed by monitoring the fluorescence intensity decrease (destaining).

Although FM dyes have contributed greatly to the field of vesicle recycling, it is not possible to determine the exact localization or morphology of individual vesicles by using conventional fluorescence microscopy. For that reason, we explain here how FM dyes can also be used as endocytic markers using electron microscopy, through photoconversion. The photoconversion technique exploits the property of fluorescent dyes to generate reactive oxygen species under intense illumination. Fluorescently labeled preparations are submerged in a solution containing diaminobenzidine (DAB) and illuminated. Reactive species generated by the dye molecules oxidize the DAB, which forms a stable, insoluble precipitate that has a dark appearance and can be easily distinguished in electron microscopy 2,3. As DAB is only oxidized in the immediate vicinity of fluorescent molecules (as the reactive oxygen species are short-lived), the technique ensures that only fluorescently labeled structures are going to contain the electron-dense precipitate. The technique thus allows the study of the exact location and morphology of actively recycling organelles.

FM dyes have been of invaluable help in the understanding of synaptic dynamics. FMs are normally followed under the fluorescent microscope during different stimulation conditions. However, photoconversion of FM dyes combined with electron microscopy allows the visualization of distinct synaptic vesicle pools, among other ultrastructure components, in synaptic boutons.

スチリル染料の光変換を使用して、シナプス小胞プールの勉強

The fusion of synaptic vesicles with the plasma membrane (exocytosis) is a required step in neurotransmitter release and neuronal communication. The ...

神経科学

Fluorescence Recovery After Photobleaching (FRAP) of Fluorescence Tagged Proteins in Dendritic Spines of Cultured Hippocampal Neurons

FRAP has been used to quantify the mobility of GFP-tagged proteins. Using a strong excitation laser, the fluorescence of a GFP-tagged protein is bleached in the region of interest. The fluorescence of the region recovers when the unbleached GFP-tagged protein from outside of the region diffuses into the region of interest. The mobility of the protein is then analyzed by measuring the fluorescence recovery rate. This technique could be used to characterize protein mobility and turnover rate.
In this study, we express the (enhanced green fluorescent protein) EGFP vector in cultured hippocampal neurons. Using the Zeiss 710 confocal microscope, we photobleach the fluorescence signal of the GFP protein in a single spine, and then take time lapse images to record the fluorescence recovery after photobleaching. Finally, we estimate the percentage of mobile and immobile fractions of the GFP in spines, by analyzing the imaging data using ImageJ and Graphpad softwares.
This FRAP protocol shows how to perform a basic FRAP experiment as well as how to analyze the data.

Fluorescence Recovery After Photobleaching FRAP of Fluorescence Tagged Proteins in Dendritic Spines of Cultured Hippocampal Neurons

FRAP has been used to quantify the mobility of Green Fluorescence Protein (GFP)-tagged proteins in cultured cells. We examined the mobile/immobile fractions of the GFP by analyzing the fluorescence recovery percentage after photobleaching. In this study, FRAP was performed at spines of hippocampal neurons.

培養海馬ニューロンの樹状突起棘の蛍光タグ融合タンパク質の光退色後蛍光回復（FRAP）

FRAP has been used to quantify the mobility of GFP-tagged proteins. Using a strong excitation laser, the fluorescence of a GFP-tagged protein is bleached ...

Analysis of Dendritic Spine Morphology in Cultured CNS Neurons

Dendritic spines are the sites of the majority of excitatory connections within the brain, and form the post-synaptic 
compartment of synapses. These structures are rich in actin and have been shown to be highly dynamic. In response to classical Hebbian plasticity 
as well as neuromodulatory signals, dendritic spines can change shape and number, which is thought to be critical for the refinement of neural 
circuits and the processing and storage of information within the brain. Within dendritic spines, a complex network of proteins link extracellular 
signals with the actin cyctoskeleton allowing for control of dendritic spine morphology and number. Neuropathological studies have demonstrated that 
a number of disease states, ranging from schizophrenia to autism spectrum disorders, display abnormal dendritic spine morphology or numbers. 
Moreover, recent genetic studies have identified mutations in numerous genes that encode synaptic proteins, leading to suggestions that these 
proteins may contribute to aberrant spine plasticity that, in part, underlie the pathophysiology of these disorders. In order to study the potential 
role of these proteins in controlling dendritic spine morphologies/number, the use of cultured cortical neurons offers several advantages. Firstly, 
this system allows for high-resolution imaging of dendritic spines in fixed cells as well as time-lapse imaging of live cells. Secondly, this in 
vitro system allows for easy manipulation of protein function by expression of mutant proteins, knockdown by shRNA constructs, or pharmacological 
treatments. These techniques allow researchers to begin to dissect the role of disease-associated proteins and to predict how mutations of these 
proteins may function in vivo.

Numerous recent studies have identified mutations in synaptic proteins associated with brain pathologies. Primary cultured cortical neurons offer great flexibility in examining the effects of these disease-associated proteins on dendritic spine morphology and motility.

培養中枢神経系ニューロンの樹状突起スパイン形態の解析

Dendritic spines are the sites of the majority of excitatory connections within the brain, and form the post-synaptic 
compartment of synapses. These ...

Quantitative Analysis of Synaptic Vesicle Pool Replenishment in Cultured Cerebellar Granule Neurons using FM Dyes

After neurotransmitter release in central nerve terminals, SVs are rapidly retrieved by endocytosis. Retrieved SVs are then refilled with neurotransmitter and rejoin the recycling pool, defined as SVs that are available for exocytosis1,2. The recycling pool can generally be subdivided into two distinct pools - the readily releasable pool (RRP) and the reserve pool (RP). As their names imply, the RRP consists of SVs that are immediately available for fusion while RP SVs are released only during intense stimulation1,2. It is important to have a reliable assay that reports the differential replenishment of these SV pools in order to understand 1) how SVs traffic after different modes of endocytosis (such as clathrin-dependent endocytosis and activity-dependent bulk endocytosis) and 2) the mechanisms controlling the mobilisation of both the RRP and RP in response to different stimuli.
FM dyes are routinely employed to quantitatively report SV turnover in central nerve terminals3-8. They have a hydrophobic hydrocarbon tail that allows reversible partitioning in the lipid bilayer, and a hydrophilic head group that blocks passage across membranes. The dyes have little fluorescence in aqueous solution, but their quantum yield increases dramatically when partitioned in membrane9. Thus FM dyes are ideal fluorescent probes for tracking actively recycling SVs. The standard protocol for use of FM dye is as follows. First they are applied to neurons and are taken up during endocytosis (Figure 1). After non-internalised dye is washed away from the plasma membrane, recycled SVs redistribute within the recycling pool. These SVs are then depleted using unloading stimuli (Figure 1). Since FM dye labelling of SVs is quantal10, the resulting fluorescence drop is proportional to the amount of vesicles released. Thus, the recycling and fusion of SVs generated from the previous round of endocytosis can be reliably quantified.
Here, we present a protocol that has been modified to obtain two additional elements of information. Firstly, sequential unloading stimuli are used to differentially unload the RRP and the RP, to allow quantification of the replenishment of specific SV pools. Secondly, each nerve terminal undergoes the protocol twice. Thus, the response of the same nerve terminal at S1 can be compared against the presence of a test substance at phase S2 (Figure 2), providing an internal control. This is important, since the extent of SV recycling across different nerve terminals is highly variable11.
Any adherent primary neuronal cultures may be used for this protocol, however the plating density, solutions and stimulation conditions are optimised for cerebellar granule neurons (CGNs)12,13.

A live fluorescence imaging technique to quantify the replenishment and mobilisation of specific synaptic vesicle (SV) pools in central nerve terminals is described. Two rounds of SV recycling are monitored in the same nerve terminals providing an internal control.

FM染料を用いて培養小脳顆粒神経細胞のシナプス小胞プールの補充の定量分析

After neurotransmitter release in central nerve terminals, SVs are rapidly retrieved by endocytosis.  Retrieved SVs are then refilled with ...

Inducing Dendritic Growth in Cultured Sympathetic Neurons

The shape of the dendritic arbor determines the total synaptic input a neuron can receive 1-3, and influences the types and distribution of these inputs 4-6. Altered patterns of dendritic growth and plasticity are associated with impaired neurobehavioral function in experimental models 7, and are thought to contribute to clinical symptoms observed in both neurodevelopmental disorders 8-10 and neurodegenerative diseases 11-13. Such observations underscore the functional importance of precisely regulating dendritic morphology, and suggest that identifying mechanisms that control dendritic growth will not only advance understanding of how neuronal connectivity is regulated during normal development, but may also provide insight on novel therapeutic strategies for diverse neurological diseases.
Mechanistic studies of dendritic growth would be greatly facilitated by the availability of a model system that allows neurons to be experimentally switched from a state in which they do not extend dendrites to one in which they elaborate a dendritic arbor comparable to that of their in vivo counterparts. Primary cultures of sympathetic neurons dissociated from the superior cervical ganglia (SCG) of perinatal rodents provide such a model. When cultured in defined medium in the absence of serum and ganglionic glial cells, sympathetic neurons extend a single process which is axonal, and this unipolar state persists for weeks to months in culture 14,15. However, the addition of either bone morphogenetic protein-7 (BMP-7) 16,17 or Matrigel 18 to the culture medium triggers these neurons to extend multiple processes that meet the morphologic, biochemical and functional criteria for dendrites. Sympathetic neurons dissociated from the SCG of perinatal rodents and grown under defined conditions are a homogenous population of neurons 19 that respond uniformly to the dendrite-promoting activity of Matrigel, BMP-7 and other BMPs of the decapentaplegic (dpp) and 60A subfamilies 17,18,20,21. Importantly, Matrigel- and BMP-induced dendrite formation occurs in the absence of changes in cell survival or axonal growth 17,18.
Here, we describe how to set up dissociated cultures of sympathetic neurons derived from the SCG of perinatal rats so that they are responsive to the selective dendrite-promoting activity of Matrigel or BMPs.

We describe a protocol for using bone morphogenetic protein-7 (BMP-7) or Matrigel to selectively induce dendritic growth in primary sympathetic neurons dissociated from the superior cervical ganglia (SCG) of perinatal rats.

培養交感神経ニューロンの樹状成長を誘導する

The shape of the dendritic arbor determines the total synaptic input a neuron can receive 1-3, and influences the types and distribution of these inputs ...

Lateral Diffusion and Exocytosis of Membrane Proteins in Cultured Neurons Assessed using Fluorescence Recovery and Fluorescence-loss Photobleaching

Membrane proteins such as receptors and ion channels undergo active trafficking in neurons, which are highly polarised and morphologically complex. This directed trafficking is of fundamental importance to deliver, maintain or remove synaptic proteins.
Super-ecliptic pHluorin (SEP) is a pH-sensitive derivative of eGFP that has been extensively used for live cell imaging of plasma membrane proteins1-2. At low pH, protonation of SEP decreases photon absorption and eliminates fluorescence emission. As most intracellular trafficking events occur in compartments with low pH, where SEP fluorescence is eclipsed, the fluorescence signal from SEP-tagged proteins is predominantly from the plasma membrane where the SEP is exposed to a neutral pH extracellular environment. When illuminated at high intensity SEP, like every fluorescent dye, is irreversibly photodamaged (photobleached)3-5. Importantly, because low pH quenches photon absorption, only surface expressed SEP can be photobleached whereas intracellular SEP is unaffected by the high intensity illumination6-10. 
FRAP (fluorescence recovery after photobleaching) of SEP-tagged proteins is a convenient and powerful technique for assessing protein dynamics at the plasma membrane. When fluorescently tagged proteins are photobleached in a region of interest (ROI) the recovery in fluorescence occurs due to the movement of unbleached SEP-tagged proteins into the bleached region. This can occur via lateral diffusion and/or from exocytosis of non-photobleached receptors supplied either by de novo synthesis or recycling (see Fig. 1). The fraction of immobile and mobile protein can be determined and the mobility and kinetics of the diffusible fraction can be interrogated under basal and stimulated conditions such as agonist application or neuronal activation stimuli such as NMDA or KCl application8,10. 
We describe photobleaching techniques designed to selectively visualize the recovery of fluorescence attributable to exocytosis. Briefly, an ROI is photobleached once as with standard FRAP protocols, followed, after a brief recovery, by repetitive bleaching of the flanking regions. This 'FRAP-FLIP' protocol, developed in our lab, has been used to characterize AMPA receptor trafficking at dendritic spines10, and is applicable to a wide range of trafficking studies to evaluate the intracellular trafficking and exocytosis.

This report describes the use of live cell imaging and photobleach techniques to determine the surface expression, transport pathways and trafficking kinetics of exogenously expressed, pH-sensitive GFP-tagged proteins at the plasma membrane of neurons.

培養神経細胞における膜タンパク質の側方拡散とエキソサイトーシスは、蛍光回復と蛍光損失光退色を用いて評価

Membrane proteins such as receptors and ion channels undergo active trafficking in neurons, which are highly polarised and morphologically complex. This ...

Detection of Protein Palmitoylation in Cultured Hippocampal Neurons by Immunoprecipitation and Acyl-Biotin Exchange (ABE)

Palmitoylation is a post-translational lipid modification involving the attachment of a 16-carbon saturated fatty acid, palmitate, to cysteine residues of substrate proteins through a labile thioester bond [reviewed in1]. Palmitoylation of a substrate protein increases its hydrophobicity, and typically facilitates its trafficking toward cellular membranes. Recent studies have shown palmitoylation to be one of the most common lipid modifications in neurons1, 2, suggesting that palmitate turnover is an important mechanism by which these cells regulate the targeting and trafficking of proteins. The identification and detection of palmitoylated substrates can therefore better our understanding of protein trafficking in neurons.
Detection of protein palmitoylation in the past has been technically hindered due to the lack of a consensus sequence among substrate proteins, and the reliance on metabolic labeling of palmitoyl-proteins with 3H-palmitate, a time-consuming biochemical assay with low sensitivity. Development of the Acyl-Biotin Exchange (ABE) assay enables more rapid and high sensitivity detection of palmitoylated proteins2-4, and is optimal for measuring the dynamic turnover of palmitate on neuronal proteins. The ABE assay is comprised of three biochemical steps (Figure 1): 1) irreversible blockade of unmodified cysteine thiol groups using N-ethylmaliemide (NEM), 2) specific cleavage and unmasking of the palmitoylated cysteine's thiol group by hydroxylamine (HAM), and 3) selective labeling of the palmitoylated cysteine using a thiol-reactive biotinylation reagent, biotin-BMCC. Purification of the thiol-biotinylated proteins following the ABE steps has differed, depending on the overall goal of the experiment.
Here, we describe a method to purify a palmitoylated protein of interest in primary hippocampal neurons by an initial immunoprecipitation (IP) step using an antibody directed against the protein, followed by the ABE assay and western blotting to directly measure palmitoylation levels of that protein, which is termed the IP-ABE assay. Low-density cultures of embryonic rat hippocampal neurons have been widely used to study the localization, function, and trafficking of neuronal proteins, making them ideally suited for studying neuronal protein palmitoylation using the IP-ABE assay. The IP-ABE assay mainly requires standard IP and western blotting reagents, and is only limited by the availability of antibodies against the target substrate. This assay can easily be adapted for the purification and detection of transfected palmitoylated proteins in heterologous cell cultures, primary neuronal cultures derived from various brain tissues of both mouse and rat, and even primary brain tissue itself.

Detection of Protein Palmitoylation in Cultured Hippocampal Neurons by Immunoprecipitation and Acyl-Biotin Exchange ABE

The reversible addition of palmitate to proteins is an important regulator of intracellular protein trafficking. This is of particular interest in neurons where many synaptic proteins are palmitoylated. We utilize a simple biochemical method to detect palmitoylated proteins in cultured neurons, which can be adapted for multiple cell types and tissues.

免疫沈降およびアシル-ビオチン所（阿部）による培養海馬神経細胞におけるタンパク質パルミトイル化の検出

Palmitoylation is a post-translational lipid  modification involving the attachment of a 16-carbon saturated fatty acid,  palmitate, to cysteine residues ...

Assaying DNA Damage in Hippocampal Neurons Using the Comet Assay

A number of drugs target the DNA repair pathways and induce cell kill by creating DNA damage. Thus, processes to directly measure DNA damage have been extensively evaluated. Traditional methods are time consuming, expensive, resource intensive and require replicating cells. In contrast, the comet assay, a single cell gel electrophoresis assay, is a faster, non-invasive, inexpensive, direct and sensitive measure of DNA damage and repair. All forms of DNA damage as well as DNA repair can be visualized at the single cell level using this powerful technique.
	The principle underlying the comet assay is that intact DNA is highly ordered whereas DNA damage disrupts this organization. The damaged DNA seeps into the agarose matrix and when subjected to an electric field, the negatively charged DNA migrates towards the cathode which is positively charged. The large undamaged DNA strands are not able to migrate far from the nucleus. DNA damage creates smaller DNA fragments which travel farther than the intact DNA. Comet Assay, an image analysis software, measures and compares the overall fluorescent intensity of the DNA in the nucleus with DNA that has migrated out of the nucleus. Fluorescent signal from the migrated DNA is proportional to DNA damage. Longer brighter DNA tail signifies increased DNA damage. Some of the parameters that are measured are tail moment which is a measure of both the amount of DNA and distribution of DNA in the tail, tail length and percentage of DNA in the tail. This assay allows to measure DNA repair as well since resolution of DNA damage signifies repair has taken place. The limit of sensitivity is approximately 50 strand breaks per diploid mammalian cell 1,2. Cells treated with any DNA damaging agents, such as etoposide, may be used as a positive control. Thus the comet assay is a quick and effective procedure to measure DNA damage.

The comet assay is an efficient way of detecting single- and double-strand breaks, including alkali-labile sites and DNA-DNA/DNA-protein cross-links on the DNA in all cells including hippocampal neurons. The method takes advantage of the differential migration of DNA in an electric field due to differences in amount of DNA damage.

コメットアッセイを用いて海馬神経細胞のDNA損傷を測定する

A number of drugs target the DNA repair pathways and induce cell kill by creating DNA damage. Thus, processes to directly measure DNA damage have been ...

Post-embedding Immunogold Labeling of Synaptic Proteins in Hippocampal Slice Cultures

Immunoelectron microscopy is a powerful tool to study biological molecules at the subcellular level. Antibodies coupled to electron-dense markers such as colloidal gold can reveal the localization and distribution of specific antigens in various tissues1. The two most widely used techniques are pre-embedding and post-embedding techniques. In pre-embedding immunogold-electron microscopy (EM) techniques, the tissue must be permeabilized to allow antibody penetration before it is embedded. These techniques are ideal for preserving structures but poor penetration of the antibody (often only the first few micrometers) is a considerable drawback2. The post-embedding labeling methods can avoid this problem because labeling takes place on sections of fixed tissues where antigens are more easily accessible. Over the years, a number of modifications have improved the post-embedding methods to enhance immunoreactivity and to preserve ultrastructure3-5.
Tissue fixation is a crucial part of EM studies. Fixatives chemically crosslink the macromolecules to lock the tissue structures in place. The choice of fixative affects not only structural preservation but also antigenicity and contrast. Osmium tetroxide (OsO4), formaldehyde, and glutaraldehyde have been the standard fixatives for decades, including for central nervous system (CNS) tissues that are especially prone to structural damage during chemical and physical processing. Unfortunately, OsO4 is highly reactive and has been shown to mask antigens6, resulting in poor and insufficient labeling. Alternative approaches to avoid chemical fixation include freezing the tissues. But these techniques are difficult to perform and require expensive instrumentation. To address some of these problems and to improve CNS tissue labeling, Phend et al. replaced OsO4 with uranyl acetate (UA) and tannic acid (TA), and successfully introduced additional modifications to improve the sensitivity of antigen detection and structural preservation in brain and spinal cord tissues7. We have adopted this osmium-free post-embedding method to rat brain tissue and optimized the immunogold labeling technique to detect and study synaptic proteins.
We present here a method to determine the ultrastructural localization of synaptic proteins in rat hippocampal CA1 pyramidal neurons. We use organotypic hippocampal cultured slices. These slices maintain the trisynaptic circuitry of the hippocampus, and thus are especially useful for studying synaptic plasticity, a mechanism widely thought to underlie learning and memory. Organotypic hippocampal slices from postnatal day 5 and 6 mouse/rat pups can be prepared as described previously8, and are especially useful to acutely knockdown or overexpress exogenous proteins. We have previously used this protocol to characterize neurogranin (Ng), a neuron-specific protein with a critical role in regulating synaptic function8,9 . We have also used it to characterize the ultrastructural localization of calmodulin (CaM) and Ca2+/CaM-dependent protein kinase II (CaMKII)10. As illustrated in the results, this protocol allows good ultrastructural preservation of dendritic spines and efficient labeling of Ng to help characterize its distribution in the spine8. Furthermore, the procedure described here can have wide applicability in studying many other proteins involved in neuronal functions.

The localization and distribution of proteins provide important information for understanding their cellular functions. The superior spatial resolution of electron microscopy (EM) can be used to determine the subcellular localization of a given antigen following immunohistochemistry. For tissues of the central nervous system (CNS), preserving structural integrity while maintaining antigenicity has been especially difficult in EM studies. Here, we adopt a procedure that has been used to preserve structures and antigens in the CNS to study and characterize synaptic proteins in rat hippocampal CA1 pyramidal neurons.

海馬スライス培養におけるシナプス蛋白のポストエンベディング免疫金ラベリング

Immunoelectron microscopy is a powerful tool to study biological molecules at the subcellular level. Antibodies coupled to electron-dense markers such as ...

Examination of Synaptic Vesicle Recycling Using FM Dyes During Evoked, Spontaneous, and Miniature Synaptic Activities

Synaptic vesicles in functional nerve terminals undergo exocytosis and endocytosis. This synaptic vesicle recycling can be effectively analyzed using styryl FM dyes, which reveal membrane turnover. Conventional protocols for the use of FM dyes were designed for analyzing neurons following stimulated (evoked) synaptic activity. Recently, protocols have become available for analyzing the FM signals that accompany weaker synaptic activities, such as spontaneous or miniature synaptic events. Analysis of these small changes in FM signals requires that the imaging system is sufficiently sensitive to detect small changes in intensity, yet that artifactual changes of large amplitude are suppressed. Here we describe a protocol that can be applied to evoked, spontaneous, and miniature synaptic activities, and use cultured hippocampal neurons as an example. This protocol also incorporates a means of assessing the rate of photobleaching of FM dyes, as this is a significant source of artifacts when imaging small changes in intensity.

We describe the use of styryl FM dyes to image synaptic vesicle recycling in functional nerve terminals. This protocol can be applied not only to evoked, but also spontaneous and miniature synaptic activities. The protocol expands the variety of synaptic events that can be effectively evaluated.

誘発、自発的、およびミニチュアシナプス活動中に、FM色素を用いたシナプス小胞のリサイクルの検討

Synaptic vesicles in functional nerve terminals undergo exocytosis and endocytosis. This synaptic vesicle recycling can be effectively analyzed using ...