우리는 칼슘 지표의 대량 로딩을 최적화에 도움이 토론에 대한 올가 Garaschuk을 인정하고 싶습니다.

<ol><li> 형광 칼슘 지표 솔루션을 준비합니다. 우리는 짧게 염료를 아세 톡시 메틸 에스테르 염료를 사용하거나, AM. 이들은 extracellularly 주입했을 때 세포에 의해 촬영 수있는 염료입니다. 우리는 일반적으로 1 ㎜의 농도에 오레곤 - 그린 BAPTA - 1 AM 또는 AM Fluo - 4를 사용합니다. AM의 염료 50 마이크로 그램의 튜브 안에 Invitrogen에서 얻을 수 있습니다. 우리가 먼저 DMSO에서 Pluronic F - 127의 20 % 솔루션을 준비합니다. 우리는 분명까지 매일 사용하기 전에 솔루션을 따뜻하게. 우리는 칼슘 표시 10 mm의 농도 15-20분에 대한 20 % Pluronic의 F-127/DMSO을 풀다. 150 NaCl, 2.5 KCl, 10 Hepes, 산도 7.4 : 우리는 다음 MM에 포함된 솔루션에서 1mM에 대한 해결책을 희석. 또한, 100 μm의 제품 Sulforhodamine 101은 일반적으로 레이블 astrocytes에 포함되어 있으며 사출 동안 피펫을 시각화. 우리는 0.49 미크론 원심 필터 (..; Garaschuk 외, 2006 Stosiek 외, 2003)로 사전에 주입에 대한 해결책을 필터링합니다. </li><li> 몇 군데로 그 지역에있는 두개의 창문을 이식. 우리는이 <a href="http://jove.com/index/details.stp?ID=680" target="_blank">목성에있는 일반적인 접근 방식을 설명</a> 하지만, 다음과 같은 수정은 칼슘 염료 주입을 위해 중요합니다 : 기본 두라 손상되지 극단적인 간병, 관심의 피질 영역 직경 2mm의 작은 craniotomy하십시오. craniotomy 이상의 장소에 coverslip을 확보하지만, 일부만 obliquely 피질을 입력 피펫을위한 공간을 허용하도록 craniotomy의 가장자리와 유리 coverslip 사이에 작은 간격을두고, craniotomy을 커버. 이전 주사로, craniotomy 주위에 치과 시멘트와 얕은 우물을합니다. 우물 방향으로 주동이의 확장 및 사출에 대한 micropipette 삽입을 허용하는 정도로 얕은해야합니다. </li><li> 현미경의 무대로 전송 마우스를 전송하고 우리와 같이, 머리를 고정 <a href="http://jove.com/index/details.stp?ID=678" target="_blank">혈액 흐름 이미징에서 비디오</a> . </li><li> 피펫 풀러를 사용하여 저항에서 2-4 메가 Ohms 저조한 팁 직경에 유리 microelectrode의 pipettes을 당기세요. microsyringe를 사용하여 유리 피펫에 칼슘 표시기 염료 믹스를로드합니다. micromanipulator를 사용하면 부드럽게 다음 잘게 40X 목표 아래에 위치하는 4X 목표를 사용하여 두뇌의 표면에 micropipette를 낮춥니다. 이미지를 보이지 않게하기 위해 거의 또는 전혀 overlying의 혈관이있다는 것을 같은 사출에 적합한 위치를 선택합니다. 두 광자 현미경을 사용하여, 피펫의 끝은 두라 아래 200 micrometers의 깊이, 시각 천천히 피질로 고급이다. 그런 다음, 압력 Picospritzer를 사용하여 1 분 10 PSI에서 염료 혼합물을 주입. 우리는 일반적으로 약 200-300 마이크론의 공간에서 구분된 오전 칼슘 색소 믹스의 2-4 주사를 제공합니다. 약간 중복되는 주사의 대량 로딩 방식은 600 x 600 마이크론 크기로 공간이 충분히 칼슘 이미징을위한 스테인드 것을 보장합니다. 확산과 뉴런에 의해 연결됩니다 염료 수 있도록, 오전 염료 혼합물의 주입 후에 이미지 1 시간 시작합니다. </li><li> - 생체내의 정의와 함께 두 광자 이미징은 카멜레온 티 - 사파이어 레이저 (800-880 nm의로 조정)과 캠브리지 기술 검류계 미러를 사용하여 두 광자 현미경을 만들어 수행합니다. 우리는 카렐 스보보다의 연구실 (Pologruto 외., 2003)에서 개발한 ScanImage 소프트웨어를 사용하여 이미지를 획득. 레이저 전원 잘 샘플 70 MW 아래 일반적이다. 전체 필드 이미지 중 초당 1.95-15.63 프레임 (256 X 64 픽셀 512 X 256 픽셀)에서 20X (NA 0.95) 또는 40X (NA 0.8) 올림푸스 목표를 사용을 찾았습니다. 라인 스캔 500 Hz에서에서 찾았습니다. 이미징 동안 동물은 빛의 isoflurane 마취 (0.6-0.9 %)에서 유지되며, 또한 37 ° C 보관 하버드 장치 온도 제어 장치를 사용하여. 치료는 가능한 한 가까운 100 호흡 / 분에 대해서 동물의 호흡 속도를 유지로 이동합니다. 마취의 사용 수준은 동물을 움직이게 낮은 수준이지만, 여전히 기록하는 자발적인 활동을 허용합니다. </li></ol>

<ol>
	<li>Garaschuk, O., Milos, R. I., Konnerth, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+bulk-loading+of+fluorescent+indicators+for+two-photon+brain+imaging+in+vivo.">Targeted bulk-loading of fluorescent indicators for two-photon brain imaging in vivo.</a> Nat Protoc. 1, (2006).</li><li>Stosiek, C., Garaschuk, O., Holthoff, K., Konnerth, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-vivo+two-photon+calcium+imaging+of+neuronal+networks.">In-vivo two-photon calcium imaging of neuronal networks.</a> Proc Natl Acad Sci USA. 100, 7319-7324 (2003).</li><li>Pologruto, T. A., Sabatini, B. L., Svoboda, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ScanImage:+flexible+software+for+operating+laser+scanning+microscopes.&amp;nbsp;&amp;nbsp;+Biomed+Eng+Online+2:13.">ScanImage: flexible software for operating laser scanning microscopes.&amp;nbsp;&amp;nbsp; Biomed Eng Online 2:13.</a> Biomed Eng Online. 2, (2003).</li></ol>

electrophysiological 녹음을 통해이 방법의 장점은 덜 침략하고 밀도의 연결의 연결을 네트워크에 활동의 기록을 허용한다는 것입니다. 이 절차를 수행할 때 그것은 두라을 손상하지 craniotomy를 수행할 때 극단적인 돌봐 기억하는 것이 중요 S. 과 경막하 출혈도 작은 금액은 크게 이미지를 흐릿하게.

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Oregon Green BAPTA1-AM</td>
<td>Reagent</td>
<td>Invitrogen</td>
<td>O-6807</td>
<td>&nbsp;</td>
<tr>
<td>Fluo 4- AM</td>
<td>Reagent</td>
<td>Invitrogen</td>
<td>F-14201</td>
<td>&nbsp;</td>
<tr>
<td>Sulforhodamine 101</td>
<td>Reagent</td>
<td>Invitrogen</td>
<td>S-359</td>
<td>&nbsp;</td>
<tr>
<td>Pluronic F-127 in DMSO</td>
<td>Reagent</td>
<td>Invitrogen</td>
<td>P-3000MP</td>
<td>&nbsp;</td>
<tr>
<td>Centrifugal Filter (0.45 micron)</td>
<td>Reagent</td>
<td>Millipore</td>
<td>UFC3 0HV 0S</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>
			<div>
					</div>

in vivo 2-photon calcium imaging in layer 2/3 of mice

네크로 텍스의 microcircuits의 네트워크 역학을 이해하기 위해서는 동시에 뉴런의 다수의 활동을 기록하는 것이 필수적입니다. - 생체내에서 두 광자 칼슘 이미징 하나는 단일 셀 해상도 고밀도의 연결 인구의 활동을 기록하는 수있는 유일한 방법입니다. 방법은 뉴런의 큰 숫자에 의해 촬영하고 마지막에 - 생체내 두 광자 현미경을 사용하여 시간 저속 칼슘 이미징과 뉴런의 활동을 기록 할 수있는 형광 칼슘 지표 염료를 주입, 두개골 이미지 창을 이온 주입으로 구성되어 있습니다. astrocyte 특정 염료의 공동 주사 하나 ast​​rocytes에서 뉴런을 차별화 할 수 있습니다. 기술은 더 나은 세포의 서로 다른 그룹의 네트워크 상호 작용을 이해하는 뉴런의 특정 subpopulations에 형광 분자를 표현 생쥐에서 수행할 수 있습니다.

Watch this Scientific Journal Video about In Vivo 2-Photon Calcium Imaging in Layer 2/3 of Mice at JoVE.com

In Vivo 2-Photon Calcium Imaging in Layer 2/3 of Mice

네크로 텍스의 microcircuits의 네트워크 역학을 이해하기 위해서는 동시에 뉴런의 다수의 활동을 기록하는 것이 필수적입니다. - 생체내에서 두 광자 칼슘 이미징 하나는 단일 셀 해상도 고밀도의 연결 인구의 활동을 기록하는 수있는 유일한 방법입니다.

레이어의 VIVO에서 2 광자 칼슘 이미징 마우스의 2 / 3

To understand network dynamics of microcircuits in the neocortex, it is essential to simultaneously record the activity of a large number of neurons .  ...

in-vivo-2-photon-calcium-imaging-in-layer-23-of-mice

Research

JoVE Journal

Biology

28.0K 조회수.  University of California, Los Angeles. 네크로 텍스의 microcircuits의 네트워크 역학을 이해하기 위해서는 동시에 뉴런의 다수의 활동을 기록하는 것이 필수적입니다. - 생체내에서 두 광자 칼슘 이미징 하나는 단일 셀 해상도 고밀도의 연결 인구의 활동을 기록하는 수있는 유일한 방법입니다.

비디오: In Vivo 2-Photon Calcium Imaging in Layer 2/3 of Mice

Dissection and 2-Photon Imaging of Peripheral Lymph Nodes in Mice

Two-photon imaging has revealed an elegant choreography of motility and cellular interactions within the lymph node under basal conditions and at the initiation of an immune response 1. Here, we present methods for adoptive transfer of labeled T cells, isolation of lymph nodes, and imaging motility of CD4+ T cells in the explanted lymph node as first described in 2002 2. Two-photon imaging of immune cells requires that the cells are fluorescently labeled, either by staining with a cell tracker dye or by expressing a fluorescent protein. We demonstrate the adoptive transfer procedure of injecting cells derived from donor mice into the tail vein of a recipient animal, where they home to lymphoid organs within approximately 15-30 min. We illustrate the isolation of a lymph node and describe methods to ensure proper mounting of the excised lymph node. Other considerations such as proper oxygenation of perfused media, temperature, and laser power are discussed. Finally, we present 3D video images of naive CD4+ T cells exhibiting steady state motility at 37&deg;C.

Two-photon imaging has uncovered lymphocyte motility and cellular interactions within the lymph node under basal conditions and durring an immune response 1. Here, we demonstrate adoptive transfer of T cells, isolation of lymph nodes, and imaging motility of CD4+ T cells in the explanted lymph node.

해부와 마우스에서 주변 림프절의 2 광자 이미징

Two-photon imaging has revealed an elegant choreography of motility and cellular interactions within the lymph node under basal conditions and at the ...

연구

생물학

In situ Imaging of the Mouse Thymus Using 2-Photon Microscopy

Two-photon Microscopy (TPM) enables us to image deep into the thymus and document the events that are important for thymocyte development. To follow the migration of individuals in a crowd of thymocytes , we generate neonatal chimeras where less than one percent of the thymocytes are derived from a donor that is transgenic for a ubiquitously express fluorescent protein. To generate these partial hematopoetic chimeras, neonatal recipients are injected with bone marrow between 3-7 days of age. After 4-6 weeks, the mouse is sacrificed and the thymus is carefully dissected and bissected preserving the architecture of the tissue that will be imaged. The thymus is glued onto a coverslip in preparation for ex vivo imaging by TPM. During imaging the thymus is kept in DMEM without phenol red that is perfused with 95% oxygen and 5% carbon dioxide and warmed to 37&deg;C. Using this approach, we can study the events required for the generation of a diverse T cell repertoire.

We present step-by-step instructions for the generation of neonatal chimeras as well as the dissection and preparation of the thymus for ex vivo imaging by 2-Photon Microscopy.

2 광자 현미경을 사용하여 마우스 Thymus의 현장 영상에서

Two-photon Microscopy (TPM) enables us to image deep into the thymus and document the events that are important for thymocyte development.  To follow the ...

A Method for 2-Photon Imaging of Blood Flow in the Neocortex through a Cranial Window

The ability to image the cerebral vasculature (from large vessels to capillaries) and record blood flow dynamics in the intact brain of living rodents is a powerful technique. Using in vivo 2-photon microscopy through a cranial window it is possible to image fluorescent dyes injected intravenously. This permits one to image the cortical vasculature and also to obtain measurements of blood flow. This technique was originally developed by David Kleinfeld and Winfried Denk. The method can be used to study blood flow dynamics during or after cerebral ischemia, in neurodegenerative disorders, in brain tumors, or in normal brain physiology. For example, it has been used to study how stroke causes shifts in blood flow direction and changes in red blood cell velocity or flux in and around the infarct. Here we demonstrate how to use 2-photon microscopy to image blood flow dynamics in the neocortex of living mice using fluorescent dyes injected into the tail vein.

Cortical blood flow dynamics can be studied in vivo by imaging fluorescent dextran dyes injected into the tail vein of rodents with 2-photon microscopy. This video shows how to image blood flow dynamics in neocortex of mice through a glass-covered cranial window preparation.

두개골의 창문을 통해 네크로 텍스의 혈류의 2 광자 이미징을위한 방법

The ability to image the cerebral vasculature (from large vessels to capillaries) and record blood flow dynamics in the intact brain of living rodents is ...

Generation of Bone Marrow Derived Murine Dendritic Cells for Use in 2-photon Imaging

Several methods for the preparation of murine dendritic cells can be found in the literature. Here, we present a method that produces greater than 85% CD11c high dendritic cells in culture that home to the draining lymph node after subcutaneous injection and present antigen to antigen specific T cells (see video). Additionally, we use Essen Instruments Incucyte to track dendritic cell maturation, where, at day 10, the morphology of the cultured cells is typical of a mature dendritic cell and &lt;85% of cells are CD11chigh. The study of antigen presentation in peripheral lymph nodes by 2-photon imaging revealed that there are three distinct phases of dendritic cell and T cell interaction1, 2. Phase I consists of brief serial contacts between highly motile antigen specific T cells and antigen carrying dendritic cells1, 2. Phase two is marked by prolonged contacts between antigen-specific T cell and antigen bearing dendritic cells1, 2. Finally, phase III is characterized by T cells detaching from dendritic cells, regaining motility and beginning to divide1, 2. This is one example of the type of antigen-specific interactions that can be analyzed by two-photon imaging of antigen-loaded cell tracker dye-labeled dendritic cells.

Antigen presentation in secondary lymphoid organs by dendritic cells is crucial for the initiation of the T cell mediated adaptive immune response. Here we demonstrate the culture of bone marrow derived murine dendritic cells, activation, and labeling for 2-photon imaging.

골수의 생성은 2 광자 영상에서 사용하기 위해 Murine 돌기 세포를 유래

Several methods for the preparation of murine dendritic cells can be found in the literature. Here, we present a method that produces greater than 85% ...

Imaging Protein-protein Interactions in vivo

Protein-protein interactions are a hallmark of all essential cellular processes. However, many of these interactions are transient, or energetically weak, preventing their identification and analysis through traditional biochemical methods such as co-immunoprecipitation. In this regard, the genetically encodable fluorescent proteins (GFP, RFP, etc.) and their associated overlapping fluorescence spectrum have revolutionized our ability to monitor weak interactions in vivo using F&ouml;rster resonance energy transfer (FRET)1-3. Here, we detail our use of a FRET-based proximity assay for monitoring receptor-receptor interactions on the endothelial cell surface.

Imaging Protein-protein Interactions in vivo

This protocol describes how to image protein-protein interactions using a FRET-based proximity assay.

이미징 단백질 - 단백질 상호 작용 생체내에</em

Protein-protein interactions are a hallmark of all essential cellular processes. However, many of these interactions are transient, or energetically weak, ...

Functional Imaging of Brown Fat in Mice with 18F-FDG micro-PET/CT

Brown adipose tissue (BAT) differs from white adipose tissue (WAT) by its discrete location and a brown-red color due to rich vascularization and high density of mitochondria. BAT plays a major role in energy expenditure and non-shivering thermogenesis in newborn mammals as well as the adults 1. BAT-mediated thermogenesis is highly regulated by the sympathetic nervous system, predominantly via &beta; adrenergic receptor 2, 3. Recent studies have shown that BAT activities in human adults are negatively correlated with body mass index (BMI) and other diabetic parameters 4-6. BAT has thus been proposed as a potential target for anti-obesity/anti-diabetes therapy focusing on modulation of energy balance 6-8. While several cold challenge-based positron emission tomography (PET) methods are established for detecting human BAT 9-13, there is essentially no standardized protocol for imaging and quantification of BAT in small animal models such as mice. Here we describe a robust PET/CT imaging method for functional assessment of BAT in mice. Briefly, adult C57BL/6J mice were cold treated under fasting conditions for a duration of 4 hours before they received one dose of 18F-Fluorodeoxyglucose (FDG). The mice were remained in the cold for one additional hour post FDG injection, and then scanned with a small animal-dedicated micro-PET/CT system. The acquired PET images were co-registered with the CT images for anatomical references and analyzed for FDG uptake in the interscapular BAT area to present BAT activity. This standardized cold-treatment and imaging protocol has been validated through testing BAT activities during pharmacological interventions, for example, the suppressed BAT activation by the treatment of &beta;-adrenoceptor antagonist propranolol 14, 15, or the enhanced BAT activation by &beta;3 agonist BRL37344 16. The method described here can be applied to screen for drugs/compounds that modulate BAT activity, or to identify genes/pathways that are involved in BAT development and regulation in various preclinical and basic studies.

Functional Imaging of Brown Fat in Mice with 18F-FDG micro-PET/CT

A method of functional imaging of mouse brown adipose tissue (BAT) is described in which cold-stimulated uptake of 18F-Fluorodeoxyglucose (FDG) in BAT is non-invasively assessed with a standardized micro-PET/CT protocol. This method is robust and sensitive to detect differences in BAT activities in mouse models.

FDG micro-PET/CT와 마우스의 브라운 지방의 기능 영상

Brown adipose tissue (BAT) differs from white adipose  tissue (WAT) by its discrete location and a brown-red color due to rich  vascularization and high ...

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) maintain the turnover of all mature blood cell lineages. The coordination of the complex signals leading to specific HSC fates relies upon the interaction between HSCs and the intricate bone marrow microenvironment, which is still poorly understood[1-2].
We describe how by combining a newly developed specimen holder for stable animal positioning with multi-step confocal and two-photon in vivo imaging techniques, it is possible to obtain high-resolution 3D stacks containing HSPCs and their surrounding niches and to monitor them over time through multi-point time-lapse imaging. High definition imaging allows detecting ex vivo labeled hematopoietic stem and progenitor cells (HSPCs) residing within the bone marrow. Moreover, multi-point time-lapse 3D imaging, obtained with faster acquisition settings, provides accurate information about HSPC movement and the reciprocal interactions between HSPCs and stroma cells.
Tracking of HSPCs in relation to GFP positive osteoblastic cells is shown as an exemplary application of this method. This technique can be utilized to track any appropriately labeled hematopoietic or stromal cell of interest within the mouse calvarium bone marrow space.

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

The nature of the interactions between hematopoietic stem and progenitor cells (HSPCs) and bone marrow niches is poorly understood. Custom hardware modifications and a multi-step acquisition protocol allow the use of two-photon and confocal microscopy to image ex vivo labeled HSPCs homed within bone marrow areas, tracking interactions and movement.

성인 마우스 두개골 골수에서 조혈 줄기 및 전구 세포의 생체 내 4 차원 추적에서

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) ...

En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries

Endothelium-derived nitric oxide (NO) produced from endothelial NO-synthase (eNOS) is one of the most important vasoprotective molecules in cardiovascular physiology. Dysfunctional eNOS such as uncoupling of eNOS leads to decrease in NO bioavailability and increase in superoxide anion (O2.&#8722;) production, and in turn promotes cardiovascular diseases. Therefore, appropriate measurement of NO and O2.&#8722; levels in the endothelial cells are pivotal for research on cardiovascular diseases and complications. Because of the extremely labile nature of NO and O2.&#8722;, it is difficult to measure NO and O2.&#8722; directly in a blood vessel. Numerous methods have been developed to measure NO and O2.&#8722; production. It is, however, either insensitive, or non-specific, or technically demanding and requires special equipment. Here we describe an adaption of the fluorescence dye method for en face simultaneous detection and visualization of intracellular NO and O2.&#8722; using the cell permeable diaminofluorescein-2 diacetate (DAF-2DA) and dihydroethidium (DHE), respectively, in intact aortas of an obesity mouse model induced by high-fat-diet feeding. We could demonstrate decreased intracellular NO and enhanced O2.&#8722; levels in the freshly isolated intact aortas of obesity mouse as compared to the control lean mouse. We demonstrate that this method is an easy technique for direct detection and visualization of NO and O2.&#8722; in the intact blood vessels and can be widely applied for investigation of endothelial (dys)function under (physio)pathological conditions.

En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries

In this article we describe an adapted relatively easy method using the fluorescence dye diaminofluorescein-2 diacetate (DAF-2DA) and dihydroethidium (DHE) for en face simultaneous detection and visualization of intracellular nitric oxide (NO) and superoxide anion (O2.&#8722;) respectively, in freshly isolated intact aortas of an obesity mouse model.

본래 동맥의 내피 층에서 산화 질소와 활성 산소의 욕실 얼굴 인식

Endothelium-derived nitric oxide (NO) produced from endothelial NO-synthase (eNOS) is one of the most important vasoprotective molecules in cardiovascular ...

Micropuncture of Bowman's Space in Mice Facilitated by 2 Photon Microscopy

Renal micropuncture and renal 2-photon imaging are seminal techniques in renal physiology. However, micropuncture is limited by dependence on conventional microscopy to surface nephron features, and 2-photon studies are limited in that interventions can only be assessed at the organ, rather than the nephron level. In particular, micropuncture studies of the glomeruli of mice have been challenged by the paucity of surface glomeruli in mice. To address this limitation in order to pursue studies of aspirate from Bowman&#39;s space in mouse physiologic models, we developed 2-photon glomerular micropuncture. We present a novel surgical preparation that allows lateral access to the kidney while preserving the required vertical imaging column for 2-photon microscopy. Administration of high molecular weight fluorescein isothiocyanate (FITC)-dextran is used to render the renal vasculature and therefore glomeruli visible for 2-photon imaging. A quantum dot-coated pipette is then introduced under stereotactic guidance to a glomerulus selected from the several to many which may be visualized within the imaging window. In this protocol, we provide details of the preparation, materials, and methods necessary to carry out the procedure. This technique facilitates previously-impossible physiologic study of the kidney, including recovery of filtrate from Bowman&#39;s space and all segments of the nephron within the imaging depth limit, about 100 &#181;m below the renal capsule. Pressure, charge and flow may all be measured using the introduced pipette. Here, we provide representative data from liquid chromatography/mass spectrometry performed on aspirate from Bowman&#39;s space. We expect this technique to have wide applicability in renal physiologic investigation.

Micropuncture of Bowman&#039;s Space in Mice Facilitated by 2 Photon Microscopy

We present use of 2-photon microscopy to place a micropipette within Bowman&#39;s urinary space in mice, combining 2 foundational techniques of renal physiology. Use of 2-photon microscopy overcomes critical limitations of conventional microscopy for micropuncture renal physiology studies.

보 먼의 공간 2 광자 현미경에 의해 촉진 생쥐에서의 Micropuncture

Renal micropuncture and renal 2-photon imaging are seminal techniques in renal physiology. However, micropuncture is limited by dependence on conventional ...

Imaging Calcium Dynamics in Subpopulations of Mouse Pancreatic Islet Cells

Pancreatic islet hormones regulate blood glucose homeostasis. Changes in blood glucose induce oscillations of cytosolic calcium in pancreatic islet cells that trigger secretion of three main hormones: insulin (from &#946;-cells), glucagon (&#945;-cells) and somatostatin (&#948;-cells). &#946;-Cells, which make up the majority of islet cells and are electrically coupled to each other, respond to the glucose stimulus as one single entity. The excitability of the minor subpopulations, &#945;-cells and &#948;-cells (making up around 20% (30%) and 4% (10%) of the total rodent1 (human2) islet cell numbers, respectively) is less predictable and is therefore of special interest.
Calcium sensors are delivered into the peripheral layer of cells within the isolated islet. The islet or a group of islets is then immobilized and imaged using a fluorescence microscope. The choice of the imaging mode is between higher throughput (wide-field) and better spatial resolution (confocal). Conventionally, laser scanning confocal microscopy is used for imaging tissue, as it provides the best separation of the signal between the neighboring cells. A wide-field system can be utilized too, if the contaminating signal from the dominating population of &#946;-cells is minimized.
Once calcium dynamics in response to specific stimuli have been recorded, data are expressed in numerical form as fluorescence intensity vs. time, normalized to the initial fluorescence and baseline-corrected, to remove the effects linked to bleaching of the fluorophore. Changes in the spike frequency or partial area under the curve (pAUC) are computed vs. time, to quantify the observed effects. pAUC is more sensitive and quite robust whereas spiking frequency provides more information on the mechanism of calcium increase.
Minor cell subpopulations can be identified using functional responses to marker compounds, such as adrenaline and ghrelin, that induce changes in cytosolic calcium in a specific populations of islet cells.

Here, we present a protocol for imaging and quantifying calcium dynamics in heterogeneous cell populations, such as pancreatic islet cells. Fluorescent reporters are delivered into the peripheral layer of cells within the islet, which is then immobilized and imaged, and per-cell analysis of the dynamics of fluorescence intensity is performed.

마우스 췌도 세포의 하위 집단에 있는 화상 진찰 칼슘 역학

Pancreatic islet hormones regulate blood glucose homeostasis. Changes in blood glucose induce oscillations of cytosolic calcium in pancreatic islet cells ...