This work was funded by the DFG (SFB 779 TPB8, Kr1879/3-1 MRK), DIP grant (MRK), EU FP7 MC-ITN NPlast (MRK), Center for Behavioral Brain Sciences (CBBS, Sahsen-Anhalt), (AK and SB), MM is a recipient of European Molecular Biology Organization (EMBO) Long-Term Fellowship (EMBO ALTF 884-2011) and Marie-Curie IEF.

1 Preparazione di acuta fettine di ippocampo di adulti Rat Brain <ol><li> Anestetizzare ratti con isoflurano. ATTENZIONE: Eseguire la procedura utilizzando un exicator chiuso, non inalare isoflurano. Assicurarsi che l&#39;animale è completamente anestetizzato. </li><li> Decapitare il ratto, rapidamente isolare il cervello, e immergerlo in precarbonated (95% O 2/5% di CO miscela di gas 2) ghiacciata soluzione Gey (composizione in mM: 130 NaCl, 4.9 KCl, 1,5 CaCl 2 · 2H 2 O , 0.3 MgSO 4 · 2H 2 O, 11 MgCl 2 · 6H 2 O, 0.23 KH 2 PO 4, 0.8 Na 2 HPO 4 · 7H 2 O, 5 Glucosio · H 2 O, 25 HEPES, 22 NaHCO 3, pH 7.32) per 30 min 1,2,10,16. </li><li> Rimuovere il cervelletto e la parte della corteccia entorinale. Separare gli emisferi corticali con un taglio medio-sagittale, quindi posizionare ciascun emisfero in giù sulla sua superficie mediale. Successivamente farea 50-70 ° taglio (50-70 ° trasversale) lungo il bordo dorsale di ogni emisfero 13,14. </li><li> Colla ciascun emisfero con la superficie appena tagliata sulla piattaforma affettatura del sistema di sezionamento. La piattaforma dovrebbe essere coperto da una soluzione di Gey ghiacciata precarbogenated. </li><li> Tagliare 350 micron 50-70 ° fette trasversali da anteriore a posteriore lato utilizzando un vibratome regolata per ridurre al minimo z oscillazione. La formazione dell&#39;ippocampo, corteccia entorinale e subicular, così come le cortecce che si trovano dorsolaterale all&#39;ippocampo faranno parte delle fette utilizzati per esperimenti 13,14. </li><li> Trasferimento fettine di ippocampo a forma di U e sommerse tipo incubatrice e incubare per almeno 2 ore a 32 ° C con carbogenated liquido cerebrospinale artificiale (ACSF contenente, in mM: 110 NaCl, 2.5 KCl, 2,5 CaCl 2 · 2H 2 O, 1.5 MgSO 4 · 2H 2 O, 1.24 KH 2 PO 4, 10 Glucosio · H 2O, 27.4 NaHCO 3, pH 7,3) 1,2,10,16. </li></ol> 2 Posizionamento Elettrodi, Baseline registrazione, e induzione di LTP <ol><li> Trasferire la fetta dell&#39;ippocampo di una camera di registrazione di tipo sommerso montato sotto un microscopio. Profumato (6-7 ml / min) con ACSF carbogenated per almeno 30 minuti a 32 ° C. </li><li> Preparare microelettrodi capillare di vetro riempito con ACSF (resistenza di punta è di 3-5 MW). </li><li> Mettere a microelettrodi di vetro riempito con ACSF nelle fibre CA1 Schaffer-collaterali per la stimolazione e nel radiatum CA1 strato per fEPSP registrazione 1,2,10 (Figura 2). La distanza tra gli elettrodi deve essere di circa 300 micron. </li><li> Evoke campo eccitatori postsinaptici Potenziali (fEPSPs) dalla stimolazione delle fibre Schaffer-collaterali con impulsi di corrente rettangolari bifasici (200 msec / polarità) in una gamma di 3-4 V. </li><li> Eseguire il test di stimolazione massima misurando la inprapporto ut-uscita e definire la forza di stimolazione come il 40% dei valori massimi fEPSP-pendenza ottenuti e mantenerla costante durante l&#39;esperimento. </li><li> Iniziare la registrazione di base per almeno 15 minuti dopo il test di stimolazione massima. Misurare le risposte a stimoli testare ogni minuto tutto l&#39;esperimento. Eseguire registrazioni di base con la stimolazione a bassa frequenza. </li><li> Registrare la linea di base per almeno 30 min. </li><li> Per l&#39;induzione tardo-LTP applicare ad alta frequenza 100 Hz tetanization composto da tre treni di stimolo 1 sec a 100 Hz con un intervallo di intertrain 5 min. Per aumentare il campo di stimolazione all&#39;interno CA1 regione 5 micron bicucullina può essere lavato in 2 minuti prima tetanization e devono essere lavati subito dopo l&#39;ultimo tetanization. </li></ol> 3 Raccolta di fette dopo induzione di LTP e Snap congelamento <ol><li> Arresto LTP registrazione 2 min o 30 min dopo tre treni di stimolazione tetanica inducono tardo-LTP. </li><li&gt; a rimuovere gli elettrodi e velocemente trasferire la fetta su una piattaforma di metallo precold messo in ghiaccio secco. Ripetere la procedura per una fetta di controllo tenuto in incubatrice a forma di U. ATTENZIONE: Utilizzare guanti durante il lavoro con ghiaccio secco. </li><li> Raccogliere ogni fetta in una provetta da 1,5 ml e conservare a -80 ° C. </li></ol> 4 Isolamento di frazioni nucleari arricchiti dalla regione CA1 dell&#39;ippocampo <ol><li> Prendere 1,5 ml provette Eppendorf con le fette congelate da -80 ° C e tenerli su ghiaccio. </li><li> Aggiungere 0,5 ml di fresco freddo TBS tampone contenente proteasi (PI) e fosfatasi (PS) inibitori, nel tubo. Incubare per 2-3 minuti e trasferire ad uno stereomicroscopio. ATTENZIONE: Usare guanti protettivi e un camice da laboratorio mentre si lavora con PI e PS. </li><li> Sezionare la regione CA1 strato piramidale dell&#39;ippocampo con due aghi. Utilizzare un ago per tenere la fetta con lo stereomicroscopio e il secondo ago per tagliare l&#39;area CA1. </li><li> Raccogliere il CA sezionato1 Le regioni da 5 fette (per ogni gruppo) in una nuova provetta da 1,5 ml contenente 50 ml di tampone di lisi (1X tampone di lisi ipotonico contenente, in mM: 10 HEPES, 1.5 MgCl2, 10 KCl, pH 7.9, con PI e PS). Si noti che questa quantità di materiale sarà sufficiente per eseguire 2-3 immunoblot. </li><li> Omogeneizzare i tessuti raccolti da un&#39;attenta pipettando su e giù. Utilizzare una pipetta 200 microlitri. Incubare il lisato in ghiaccio per 5-7 minuti per consentire alle cellule a gonfiarsi. </li><li> Prendete 2 ml di lisato, goccia su un vetrino microscopico, e visualizzare il gonfiore delle cellule al microscopio in campo chiaro. Con una corretta gonfiore delle cellule nuclei appaiono come rotondo strutture intatte. </li><li> Raccogliere 20 ml di campione in una nuova provetta da 1,5 ml come &#39;frazione omogeneizzato&#39;. Aggiungere 8 ml di denaturazione 4x tampone campione SDS. </li><li> Centrifugare i restanti lisati a 11.000 rpm per 1 min. </li><li> Raccogliere con cautela il surnatante dalla cima (&#39;frazione citosolica&#39;), transfer in un nuovo tubo e aggiungere 20 ml di tampone campione 4x. </li><li> Risospendere il pellet in 60 ml di tampone ipotonico e aggiungere 20 ml di tampone campione 4x. Questa frazione è indicato come un &#39;frazione arricchita nucleare&#39;. </li><li> Omogenato, citosolico, e le frazioni arricchite nucleari possono essere conservati a -20 ° C o -80 ° C per immunoblotting tardi. </li></ol> 5. Immunoblotting semiquantitativa di proteine ​​Synapto-nucleari <ol><li> Scongelare i campioni e farli bollire per 5 min a 95 ° C. </li><li> Prendere 5 ml di ogni frazione e determinare la concentrazione di proteine ​​da amido di prova nero o prova BCA. </li><li> Carico pari quantità di campioni di proteine ​​da omogenato, frazioni arricchite citoplasmatici e nucleari su SDS-PAGE. I campioni di controllo e fette LTP devono essere posizionati sullo stesso gel per il confronto diretto. </li><li> Eseguire una procedura di western-blotting standard (trasferimento umido è consigliato). </li><li> Sonda le membrane con tegli anticorpi di scelta. Successivamente le stesse macchie (o gli stessi campioni eseguiti in parallelo) possono essere sondati con un pennarello citoplasmatica - enolase2 neurone specifica (NSE2) e marcatore nucleare - NeuN e un anticorpo actina come controllo di caricamento. </li></ol> Analisi 6. Dati <ol><li> L&#39;efficienza di induzione di LTP può essere analizzato dal software Clampfit. La pendenza media di registrazioni di base è stato confrontato con le piste dopo tetanization utilizzando ANOVA a due vie, p &lt;0.05 è stato considerato significativamente differenti. I valori di pendenza fEPSP sono stati rappresentati nei diagrammi come media ± SEM </li><li> Per la quantificazione di immunoblot, scanditi il ​​film autoradiografica e analizzare la densità integrata delle bande proteiche da ImageJ o bande di fluorescenza con un sistema di Licor. I valori delle bande immunoreattive devono essere normalizzati per il controllo di carico e assorbente. Per il confronto del controllo e gruppi di LTP può essere utilizzato un nonparametrical Mann-Whitney U-test. </li></ol><table border="0"cellpadding = &quot;0&quot; cellspacing = &quot;0&quot;&gt; <tbody><tr><td> Nome del buffer </td><td> Reagente </td><td> Concentrazione (mM) </td><td> Quantità </td><td> Commenti / Descrizione </td></tr><tr><td> Di Gey soluzione (pH: 7.3 ~ 7.4) </td><td> NaCl </td><td> 130 </td><td> 7.6 g </td><td> filtrazione sterile </td></tr><tr><td> 1.000 ml </td><td> KCl </td><td> 4.9 </td><td> 0.37 g </td><td></td></tr><tr><td></td><td> CaCl 2 · 2H 2 O </td><td> 1.5 </td><td> 0.22 g </td><td></td></tr><tr><td></td><td> MgSO 4 · 2H 2 O </td><td> 0.3 </td><td> 0,0739 g </td><td></td></tr><tr><td></td><td> MgCl 2 · 6H 2 O </td><td> 11 </td><td> 2.24 g </td><td></td></tr><tr><td></td><td> KH 2 PO 4 </td><td> 0.23 </td><td> 0,0313 g </td><td></td></tr><tr><td></td><td> Na 2 HPO 4 · 7H 2 O </td><td> 0.8 </td><td> 0,2145 g </td><td></td></tr><tr><td></td><td> Glucosio · H 2 O </td><td> 5 </td><td> 0,9909 g </td><td></td></tr><tr><td></td><td> HEPES </td><td> 25 </td><td> 5.96 g </td><td></td></tr><tr><td></td><td> NaHCO3 </td><td> 22 </td><td> 1.85 g </td><td></td></tr><tr><td> ACSF (pH: 7.3 ~ 7.4) </td><td> NaCl </td><td> 110 </td><td> 6,428 g </td><td> filtrazione sterile </td></tr><tr><td> 1.000 ml </td><td> KCl </td><td> 2.5 </td><td> 0,1865 g </td><td></td></tr><tr><td></td><td> CaCl 2 · 2H 2 O </td><td> 2.5 </td><td> 0,368 g </td><td></td></tr><tr><td></td><td> MgSO 4 · 2H 2 O </td><td> 1.5 </td><td> 0,370 g </td&gt; <td></td></tr><tr><td></td><td> KH 2 PO 4 </td><td> 1.24 </td><td> 0,169 g </td><td></td></tr><tr><td></td><td> Glucosio · H 2 O </td><td> 10 </td><td> 1,9817 g </td><td></td></tr><tr><td></td><td> NaHCO3 </td><td> 27.4 </td><td> 2.3 g </td><td></td></tr><tr><td> 1x ipotonico tampone (pH: 7,9) </td><td> HEPES </td><td> 10 </td><td> 0.23 g </td><td></td></tr><tr><td> 100 ml </td><td> MgCl 2 · 6H 2 O </td><td> 1.5 </td><td> 0,0304 g </td><td></td></tr><tr><td></td><td> KCl </td><td> 10 </td><td> 0,07455 g </td><td></td></tr></tbody></table> Tabella 1 Buffer.

<ol>
	<li>Behnisch, 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=Nuclear+translocation+of+Jacob+in+hippocampal+neurons+after+stimuli+inducing+long-term+potentiation+but+not+long-term+depression.">Nuclear translocation of Jacob in hippocampal neurons after stimuli inducing long-term potentiation but not long-term depression.</a> PLoS One. 6 (2), e17276 (2011).</li><li>Cai, F., Frey, J. U., Sanna, P. P., Behnisch, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+degradation+by+the+proteasome+is+required+for+synaptic+tagging+and+the+heterosynaptic+stabilization+of+hippocampal+late-phase+long-term+potentiation.">Protein degradation by the proteasome is required for synaptic tagging and the heterosynaptic stabilization of hippocampal late-phase long-term potentiation.</a> Neuroscience. 169 (4), 1520-1526 (2010).</li><li>Chapman, C. A., Perez, Y., Lacaille, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+GABA(A)+inhibition+on+the+expression+of+long-term+potentiation+in+CA1+pyramidal+cells+are+dependent+on+tetanization+parameters.">Effects of GABA(A) inhibition on the expression of long-term potentiation in CA1 pyramidal cells are dependent on tetanization parameters.</a> Hippocampus. 8 (3), 289-298 (1998).</li><li>Ch'ng, T. H., Uzgil, B., Lin, P., Avliyakulov, N. K., O'Dell, T. J., Martin, K. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activity-dependent+transport+of+the+transcriptional+coactivator+CRTC1+from+synapse+to+nucleus.">Activity-dependent transport of the transcriptional coactivator CRTC1 from synapse to nucleus.</a> Cell. 150 (1), 207-221 (2012).</li><li>Dieterich, D. C., 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=Caldendrin-Jacob:+a+protein+liaison+that+couples+NMDA+receptor+signalling+to+the+nucleus.">Caldendrin-Jacob: a protein liaison that couples NMDA receptor signalling to the nucleus.</a> PLoS Biol. 6 (2), e34 (2008).</li><li>Fainzilber, M., Budnik, V., Segal, R. A., Kreutz, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=From+synapse+to+nucleus+and+back+again--communication+over+distance+within+neurons.">From synapse to nucleus and back again--communication over distance within neurons.</a> J. Neurosci. 31 (45), 16045-16048 (2011).</li><li>Hardingham, G. E., Bading, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synaptic+versus+extrasynaptic+NMDA+receptor+signalling:+implications+for+neurodegenerative+disorders.">Synaptic versus extrasynaptic NMDA receptor signalling: implications for neurodegenerative disorders.</a> Nat. Rev. Neurosci. 11 (10), 682-696 (2010).</li><li>Ivanov, A., 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=Opposing+role+of+synaptic+and+extrasynaptic+NMDA+receptors+in+regulation+of+the+extracellular+signal-regulated+kinases+(ERK)+activity+in+cultured+rat+hippocampal+neurons.">Opposing role of synaptic and extrasynaptic NMDA receptors in regulation of the extracellular signal-regulated kinases (ERK) activity in cultured rat hippocampal neurons.</a> J. Physiol. 57, 789-798 (2006).</li><li>Jordan, B. A., Kreutz, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nucleocytoplasmic+protein+shuttling:+the+direct+route+in+synapse-to-nucleus+signaling.">Nucleocytoplasmic protein shuttling: the direct route in synapse-to-nucleus signaling.</a> Trends Neurosci. 32 (7), 392-401 (2009).</li><li>Karpova, A., 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=Encoding+and+transducing+the+synaptic+or+extrasynaptic+origin+of+NMDA+receptor+signals+to+the+nucleus.">Encoding and transducing the synaptic or extrasynaptic origin of NMDA receptor signals to the nucleus.</a> Cell. 152 (5), 1119-1133 (2013).</li><li>Kim, M. J., Dunah, A. W., Wang, Y. T., Sheng, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+roles+of+NR2A-+and+NR2B-containing+NMDA+receptors+in+Ras-ERK+signaling+and+AMPA+receptor+trafficking.">Differential roles of NR2A- and NR2B-containing NMDA receptors in Ras-ERK signaling and AMPA receptor trafficking.</a> Neuron. 46, 745-760 (2005).</li><li>Lai, K. O., Zhao, Y., Ch'ng, T. H., Martin, K. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Importin-mediated+retrograde+transport+of+CREB2+from+distal+processes+to+the+nucleus+in+neurons.">Importin-mediated retrograde transport of CREB2 from distal processes to the nucleus in neurons.</a> Proc. Natl. Acad. Sci. U.S.A. 105 (44), 17175-17180 (2008).</li><li>Leutgeb, J. K., Frey, J. U., Behnisch, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=LTP+in+cultured+hippocampal-entorhinal+cortex+slices+from+young+adult+(P25-30)+rats.">LTP in cultured hippocampal-entorhinal cortex slices from young adult (P25-30) rats.</a> J. Neurosci. Methods. 130 (1), 19-32 (2003).</li><li>Leutgeb, J. K., Frey, J. U., Behnisch, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single+cell+analysis+of+activity-dependent+cyclic+AMP-responsive+element-binding+protein+phosphorylation+during+long-lasting+long-term+potentiation+in+area+CA1+of+mature+rat+hippocampal-organotypic+cultures.">Single cell analysis of activity-dependent cyclic AMP-responsive element-binding protein phosphorylation during long-lasting long-term potentiation in area CA1 of mature rat hippocampal-organotypic cultures.</a> Neuroscience. 131 (3), 601-610 (2005).</li><li>Perlson, E., Hanz, S., Ben-Yaakov, K., Segal-Ruder, Y., Seger, R., Fainzilber, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vimentin-dependent+spatial+translocation+of+an+activated+MAP+kinase+in+injured+nerve.">Vimentin-dependent spatial translocation of an activated MAP kinase in injured nerve.</a> Neuron. 45 (5), 715-726 (2005).</li><li>Xiang, 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=Long-term+maintenance+of+mature+hippocampal+slices+in+vitro.">Long-term maintenance of mature hippocampal slices in vitro.</a> J. Neurosci. Methods. 98 (2), 145-154 (2000).</li><li>Zhao, M., Adams, J. P., Dudek, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pattern-dependent+role+of+NMDA+receptors+in+actin+potential+generation:+consequences+on+extracellular+signal-regulated+kinase+activation.">Pattern-dependent role of NMDA receptors in actin potential generation: consequences on extracellular signal-regulated kinase activation.</a> J. Neurosci. 25 (30), 7032-7039 (2005).</li></ol>

The authors have nothing to disclose.

I passi descritti nel protocollo di cui sopra forniscono una guida come preparare ippocampale acuta affettato da giovani o adulti ratti, induce e registrare LTP, rapidamente sezionare zona stimolata di slice, e preparare frazione arricchita nucleare per lo studio di attività dinamica delle proteine ​​dipendenti. Questo approccio deriva dalla combinazione di diversi metodi utilizzati indipendentemente l&#39;uno dall&#39;altro. Abbiamo ottimizzato il flusso di lavoro e fornire sufficienti dettagli per il principiante...

Synaptic N-metil-D-aspartato-recettori (NMDARs) svolgono un ruolo cruciale nella plasticità sinaptica e la sopravvivenza delle cellule di segnalazione, mentre l&#39;attivazione di NMDARs extrasinaptica può innescare neurodegenerazione e la morte cellulare. Questi cambiamenti dipendono da / attività regolamentata espressione genica dipendente strettamente controllata e, quindi, richiedono una costante comunicazione tra sinapsi e dendriti attivati ​​e il nucleo 7. Il MAP chinasi ERK1 / 2 sono effettori a valle di NMDARs sinaptiche segnalazione e sono coinvolti nella espressione genica NMDAR-attivazione-indotta, considerando che la segnalazione via NMDAR extrasinaptica non ha o un effetto inibitorio sulla ERK1 / 2 attività di 8,11. Ci sono certo numero di proteine ​​che hanno dimostrato di navetta tra dendriti distali e il nucleo. Molte di queste proteine ​​contengono un segnale di localizzazione nucleare e sono attivamente trasportati lungo microtubuli in un dineina e modo importina-dipendente al nucleo 6,9. Interestingly, alcuni di questi messaggeri solo transito al nucleo in risposta a specifici stimoli sinaptici. Ad esempio, il trasporto retrogrado di ciclico elemento di risposta AMP binding protein 2 (CREB2) è indotta da LTD chimica, ma non LTP 12. Stimolazione sinaptica NMDAR-dipendente localizzata guida coactivator trascrizionale CREB-regolata (CRTC1) nel nucleo, un processo di traslocazione, che è coinvolto nel lungo termine plasticità ippocampale 4. E &#39;stato recentemente dimostrato che la proteina messaggero Giacobbe trasloca al nucleo dopo che entrambi, l&#39;attivazione NMDAR sinaptica e extrasinaptica e regola gene CREB dipendente trascrizione 5. L&#39;origine sinaptica o extrasinaptica del segnale è codificato in una modificazione post-traslazionale di Giacobbe. Attività sinaptica induce ERK1 / 2 fosforilazione dipendente di Giacobbe a serina cruciale alla posizione 180 (pJacobS 180), che è un requisito per la successiva traslocazione al nucleo nella cultura ippocampale primaria. Inoltre, in CA1 neuroni di acuta fettine di ippocampo pJacobS 180 trasloca nel nucleo dopo Schaffer collaterale LTP ma non LTD 1,10. pS180 Jacob porta ad un aumento dell&#39;espressione dei geni legati plasticità e l&#39;espressione genica feed torna alla funzione sinaptica. In netto contrasto, Giacobbe che trasloca nel nucleo dopo l&#39;attivazione NMDARs extrasinaptica non è fosforilata in Ser180 e può essere associata a complesso proteico diverso nel nucleo causando &#39;CREB spento&#39; e una ritrattazione di contatti sinaptici 10. Maggior parte degli studi pubblicati sulla importazione nucleare di Synapto-nucleare proteina messenger sono stati condotti in colture primarie neuronali dissociate. Pertanto, sarebbe interessante vedere se questi risultati possono essere riprodotti in fisiologicamente più rilevanti condizioni con fettine di ippocampo in cui la connettività e la funzione neuronale sono molto meglio conservati. Qui vi presentiamo un protocollo ottimizzato per la valutazione LTP-dependent traslocazione nucleare di messaggeri della proteina mediante immunoblotting. Questo metodo è adatto per analizzare l&#39;attività dipendente fosforilazione di proteine ​​in una frazione nucleare rudimentale anche. In particolare, l&#39;attuale protocollo prevede la preparazione di acuta fettine di ippocampo CA1, induzione, e la registrazione di LTP. Avanti, regione CA1 viene sezionato al microscopio per isolare la regione stimolata. Abbiamo combinato e modificato il protocollo per l&#39;isolamento nucleare fornito da CellLytic nucleare Extraction Kit con le modifiche introdotte dal Zhao e colleghi 17. La procedura di ottimizzazione comprende la lisi delle regioni CA1 sezionati in tampone ipotonico permettendo rigonfiamento delle cellule e il rilascio di nuclei. Lisi cellulare e la morfologia nuclei possono essere determinati mediante esame microscopico. Arricchimento nucleare viene raggiunto da una breve fase di centrifugazione. Immunoblotting con anticorpi contro NeuN e NSE2, marcatori specifici delle frazioni nucleari e citosoliche, indica che questo approccio può essere utilizzato come un velocee il protocollo riproducibile per isolare queste frazioni subcellulari e studiare molto labili modificazioni post-traduzionali come fosforilazione proteica. Inoltre, questo metodo è vantaggioso per piccoli campioni di tessuto provenienti da regioni CA1 sezionati di fettine ippocampali e può essere usato in combinazione per immunoistochimica di fettine ippocampali.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 1. Equipment</td>
		</tr>
		<tr>
			<td>CED 1401 AD/DA converter</td>
			<td>Cambridge Electronics Design, UK</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Axopatch 200B amplifier</td>
			<td>Axon&#65292;USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td><a href="http://www.iciba.com/data_acquisition_system">Axon Digidata acquisition system</a></td>
			<td>Axon&#65292;USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Clampex 10.0 Data acquisition and analysis software</td>
			<td>Axon&#65292;USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Leica microscope</td>
			<td>Leica TCS SP2&#65292;Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>P-97 Standard microelectrode puller</td>
			<td>Sutter&#65292;USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td><a href="http://www.iciba.com/stereomicroscope">Stereomicroscope</a></td>
			<td>Leica</td>
			<td>Leica S4E, Germany</td>
			<td></td>
		</tr>
		<tr>
			<td>Vibrotome</td>
			<td>Leica VT1000S, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Isolated pulse stimulator</td>
			<td>Model2100, A-M systmes, USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Thermo Scientific, HERAEUS, FRSCO17</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>SDS-PAGE system</td>
			<td>BIORAD</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cooler</td>
			<td>JULABO</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bright field Microscope</td>
			<td>NIKON ECLIPSE TS100</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture incubator</td>
			<td>Thermo Electron Corporation, HERAEUS</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Micromanipulator</td>
			<td>Luigs &#38; Neumann, SM-5, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Blotting chamber and electric power supplier</td>
			<td>Hoefer Scientific Instruments, San Francisco</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cooler</td>
			<td>Julabo, F12</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Thermo Scientific, Heraeus, FRESCO 17</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Submerged type Recording Chamber</td>
			<td>custom made</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>U-shape and submerged type incubator&#160;</td>
			<td>custom made</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Small surgical scissors</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Scalpel</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Thin spatula</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic Pasteur pipette</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic culture dish&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bunsen beaker</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 2. Reagents</td>
		</tr>
		<tr>
			<td>Name of Reagent</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>ROTH</td>
			<td>Art.-Nr.3957.1</td>
			<td>&#8805;99.5%, p.a.,ACS,ISO</td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>ROTH</td>
			<td>Art.-Nr.6781.1</td>
			<td>&#8805;99.5%, p.a.,ACS,ISO</td>
		</tr>
		<tr>
			<td>CaCl2&#183;2H2O</td>
			<td>MERCK</td>
			<td>1.02382.0500</td>
			<td>pro analysi</td>
		</tr>
		<tr>
			<td>MgSO4&#183;2H2O</td>
			<td>MERCK</td>
			<td>5886.05</td>
			<td>pro analysi</td>
		</tr>
		<tr>
			<td>MgCl2&#183;6H2O</td>
			<td>AppliChem</td>
			<td>CAS-NO: 7791-18-6; EC-NO:2320946</td>
			<td>for Molecularbiology</td>
		</tr>
		<tr>
			<td>KH2PO4</td>
			<td>MERCK</td>
			<td>12034.025</td>
			<td>for Molecularbiology</td>
		</tr>
		<tr>
			<td>Na2HPO4&#183;2H2O</td>
			<td>MERCK</td>
			<td>1.06574.1000</td>
			<td>extra pure</td>
		</tr>
		<tr>
			<td>Glucose&#183;H2O</td>
			<td>ROTH</td>
			<td>Art.-Nr.6887.1</td>
			<td>for Molecularbiology</td>
		</tr>
		<tr>
			<td>Hepes</td>
			<td>ROTH</td>
			<td>Art.-Nr.9105.4</td>
			<td>PUFFERAN, &#8805;99.5%, p.a.</td>
		</tr>
		<tr>
			<td>NaHCO3</td>
			<td>MERCK</td>
			<td>1.06329.1000</td>
			<td>pro analysi</td>
		</tr>
		<tr>
			<td>Protease inhibitor Coctail</td>
			<td>ROCHE</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphostop</td>
			<td>ROCHE</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bicuculline</td>
			<td>Tocris bioscience</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Isofluran</td>
			<td>Baxter</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 4. Antibodies</td>
		</tr>
		<tr>
			<td>Primary antibodies</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Species</td>
		</tr>
		<tr>
			<td>pJac-s180</td>
			<td>Biogenes/ purified</td>
			<td></td>
			<td>rabbit (dil. 1:100)</td>
		</tr>
		<tr>
			<td>NeuN</td>
			<td>Milipore</td>
			<td>MAB377</td>
			<td>mouse (dil. 1:1,000)</td>
		</tr>
		<tr>
			<td>NSE</td>
			<td>Cell Signaling</td>
			<td>D20H2</td>
			<td>rabbit (dil. 1:1,000)</td>
		</tr>
		<tr>
			<td>beta-actin</td>
			<td>Sigma</td>
			<td>A-5441</td>
			<td>mouse (dil. 1:5,000)</td>
		</tr>
		<tr>
			<td>Secondary antibodies</td>
			<td></td>
			<td></td>
			<td>Species</td>
		</tr>
		<tr>
			<td>IgG HRP Conjugated</td>
			<td>DAKO</td>
			<td></td>
			<td>goat anti - mouse (1:5,000)</td>
		</tr>
		<tr>
			<td>IgG HRP Conjugated</td>
			<td>NEB</td>
			<td></td>
			<td>goat anti - rabbit (1:5,000)</td>
		</tr>
	</tbody>
</table>

isolation of ca1 nuclear enriched fractions from hippocampal slices to study activity-dependent nuclear import of synapto-nuclear messenger proteins

Studiare attività di espressione della proteina dipendente, traslocazione subcellulare, o fosforilazione è essenziale per comprendere i meccanismi cellulari alla base della plasticità sinaptica. Il potenziamento a lungo termine (LTP) e depressione a lungo termine (LTD) indotta in fettine di ippocampo acute sono ampiamente accettati come modelli cellulari di apprendimento e memoria. Ci sono numerosi studi che utilizzano approcci di imaging cellulare o immunoistochimica dal vivo per visualizzare l&#39;attività dinamica delle proteine ​​dipendenti. Tuttavia questi metodi si basano sulla idoneità degli anticorpi per immunoistochimica o sovraespressione di proteine ​​fluorescenza-tagged in singoli neuroni. Immunoblotting di proteine ​​è un metodo alternativo che fornisce una conferma indipendente dei risultati. Il primo fattore limitante nella preparazione di frazioni subcellulari di singoli fettine di ippocampo tetanized è la bassa quantità di materiale. In secondo luogo, la procedura di gestione è fondamentale perché manipolazioni, anche molto brevi e minori di living fette potrebbe indurre l&#39;attivazione di alcune cascate di segnalazione. Qui si descrive un flusso di lavoro ottimizzato al fine di ottenere un quantitativo sufficiente della frazione arricchita nucleare di purezza sufficiente dalla regione CA1 di fettine di ippocampo acute di cervello di ratto. Come esempio rappresentativo mostriamo che la ERK1 / 2 forma fosforilata della proteina messaggero Synapto-nucleare Jacob trasloca attivamente al nucleo dopo induzione di LTP e può essere rilevato in una frazione arricchita nucleare dai neuroni CA1.

Abbiamo precedentemente dimostrato che la Synapto-nucleare proteina messenger Giacobbe si accumula nel nucleo dopo l&#39;induzione di LTP, ma non LTD 1. Inoltre, traslocazione di Giacobbe dopo stimolazione sinaptica richiede l&#39;attivazione di MAPK ERK1 / 2 e la fosforilazione di Giacobbe a Ser180 (Figura 1). Fosforilata Jacob trasloca al nucleo in modo importina-dipendente e lo stato fosforilato può essere conservato per lunghi periodi di tempo prolungati per associazione con il filamento...

Watch this Scientific Journal Video about Isolation of CA1 Nuclear Enriched Fractions from Hippocampal Slices to Study Activity-dependent Nuclear Import of Synapto-nuclear Messenger Proteins at JoVE.c

Isolation of CA1 Nuclear Enriched Fractions from Hippocampal Slices to Study Activity-dependent Nuclear Import of Synapto-nuclear Messenger Proteins

Forniamo un protocollo dettagliato per l&#39;induzione del potenziamento a lungo termine nella regione CA1 dell&#39;ippocampo e il successivo isolamento di frazioni arricchite nucleari dalla zona tetanized della fetta. Questo approccio può essere utilizzato per determinare l&#39;attività dipendente di importazione proteina nucleare in modelli cellulari di apprendimento e memoria.

Isolamento di CA1 nucleari arricchiti Frazioni di fettine di ippocampo per studiare l&#39;attività-dipendente nucleare Importazione di Messenger proteine ​​Synapto-nucleari

Studying activity dependent protein expression, subcellular translocation, or phosphorylation is essential to understand the underlying cellular ...

isolation-ca1-nuclear-enriched-fractions-from-hippocampal-slices-to

Research

JoVE Journal

Neuroscience

12.0K Views.  Leibniz Institute for Neurobiology.  Forniamo un protocollo dettagliato per l'induzione del potenziamento a lungo termine nella regione CA1 dell'ippocampo e il successivo isolamento di frazioni arricchite nucleari dalla zona tetanized della fetta. Questo approccio può essere utilizzato per determinare l'attività dipendente di importazione proteina nucleare in modelli cellulari di apprendimento e memoria. 

Video: Isolation of CA1 Nuclear Enriched Fractions from Hippocampal Slices to Study Activity-dependent Nuclear Import of Synapto-nuclear Messenger Proteins

Preparation of Acute Hippocampal Slices from Rats and Transgenic Mice for the Study of Synaptic Alterations during Aging and Amyloid Pathology

The rodent hippocampal slice preparation is perhaps the most broadly used tool for investigating mammalian synaptic function and plasticity. The hippocampus can be extracted quickly and easily from rats and mice and slices remain viable for hours in oxygenated artificial cerebrospinal fluid. Moreover, basic electrophysisologic techniques are easily applied to the investigation of synaptic function in hippocampal slices and have provided some of the best biomarkers for cognitive impairments. The hippocampal slice is especially popular for the study of synaptic plasticity mechanisms involved in learning and memory. Changes in the induction of long-term potentiation and depression (LTP and LTD) of synaptic efficacy in hippocampal slices (or lack thereof) are frequently used to describe the neurologic phenotype of cognitively-impaired animals and/or to evaluate the mechanism of action of nootropic compounds. This article outlines the procedures we use for preparing hippocampal slices from rats and transgenic mice for the study of synaptic alterations associated with brain aging and Alzheimer's disease (AD)1-3. Use of aged rats and AD model mice can present a unique set of challenges to researchers accustomed to using younger rats and/or mice in their research. Aged rats have thicker skulls and tougher connective tissue than younger rats and mice, which can delay brain extraction and/or dissection and consequently negate or exaggerate real age-differences in synaptic function and plasticity. Aging and amyloid pathology may also exacerbate hippocampal damage sustained during the dissection procedure, again complicating any inferences drawn from physiologic assessment. Here, we discuss the steps taken during the dissection procedure to minimize these problems. Examples of synaptic responses acquired in "healthy" and "unhealthy" slices from rats and mice are provided, as well as representative synaptic plasticity experiments. The possible impact of other methodological factors on synaptic function in these animal models (e.g. recording solution components, stimulation parameters) are also discussed. While the focus of this article is on the use of aged rats and transgenic mice, novices to slice physiology should find enough detail here to get started on their own studies, using a variety of rodent models.

This article outlines procedures for preparing hippocampal slices from rats and transgenic mice for the study of synaptic alterations associated with brain aging and age-related neurodegenerative diseases, such as Alzheimer&#x2019;s disease.

Preparazione di acuta fettine di ippocampo di ratti e topi transgenici per lo studio delle alterazioni sinaptiche durante l&#39;invecchiamento e Amiloide Patologia

The rodent hippocampal slice preparation is perhaps the most broadly used tool for investigating mammalian synaptic function and plasticity. The ...

Ricerca

Neuroscienze

Vibrodissociation of Neurons from Rodent Brain Slices to Study Synaptic Transmission and Image Presynaptic Terminals

Mechanical dissociation of neurons from the central nervous system has the advantage that presynaptic boutons remain attached to the isolated neuron of interest. This allows for examination of synaptic transmission under conditions where the extracellular and postsynaptic intracellular environments can be well controlled. A vibration-based technique without the use of proteases, known as vibrodissociation, is the most popular technique for mechanical isolation. A micropipette, with the tip fire-polished to the shape of a small ball, is placed into a brain slice made from a P1-P21 rodent. The micropipette is vibrated parallel to the slice surface and lowered through the slice thickness resulting in the liberation of isolated neurons. The isolated neurons are ready for study within a few minutes of vibrodissociation. This technique has advantages over the use of primary neuronal cultures, brain slices and enzymatically isolated neurons including: rapid production of viable, relatively mature neurons suitable for electrophysiological and imaging studies; superior control of the extracellular environment free from the influence of neighboring cells; suitability for well-controlled pharmacological experiments using rapid drug application and total cell superfusion; and improved space-clamp in whole-cell recordings relative to neurons in slice or cell culture preparations. This preparation can be used to examine synaptic physiology, pharmacology, modulation and plasticity. Real-time imaging of both pre- and postsynaptic elements in the living cells and boutons is also possible using vibrodissociated neurons. Characterization of the molecular constituents of pre- and postsynaptic elements can also be achieved with immunological and imaging-based approaches.

This report demonstrates a technique for mechanical isolation of individual viable neurons retaining attached presynaptic boutons. Vibrodissociated neurons have the advantages of rapid production, excellent pharmacological control and improved space-clamp without influence from neighboring cells. This method can be used for imaging of synaptic elements and patch-clamp recording.

Vibrodissociation di neuroni da fettine di cervello di roditore studio di trasmissione sinaptica e Immagine terminali presinaptici

Mechanical dissociation of neurons from the central nervous system has the advantage that presynaptic boutons remain attached to the isolated neuron of ...

Isolation and Culture of Hippocampal Neurons from Prenatal Mice

Primary cultures of rat and murine hippocampal neurons are widely used to reveal cellular mechanisms in neurobiology. By isolating and growing individual neurons, researchers are able to analyze properties related to cellular trafficking, cellular structure and individual protein localization using a variety of biochemical techniques. Results from such experiments are critical for testing theories addressing the neural basis of memory and learning. However, unambiguous results from these forms of experiments are predicated on the ability to grow neuronal cultures with minimum contamination by other brain cell types. In this protocol, we use specific media designed for neuron growth and careful dissection of embryonic hippocampal tissue to optimize growth of healthy neurons while minimizing contaminating cell types (i.e. astrocytes). Embryonic mouse hippocampal tissue can be more difficult to isolate than similar rodent tissue due to the size of the sample for dissection. We show detailed dissection techniques of hippocampus from embryonic day 19 (E19) mouse pups. Once hippocampal tissue is isolated, gentle dissociation of neuronal cells is achieved with a dilute concentration of trypsin and mechanical disruption designed to separate cells from connective tissue while providing minimum damage to individual cells. A detailed description of how to prepare pipettes to be used in the disruption is included. Optimal plating densities are provided for immuno-fluorescence protocols to maximize successful cell culture. The protocol provides a fast (approximately 2 hr) and efficient technique for the culture of neuronal cells from mouse hippocampal tissue.

We provide a protocol for the culture of highly purified hippocampal neurons from prenatal mouse brains without the use of a feeder glial cell layer.

Isolamento e la coltura di neuroni ippocampali da topi prenatali

Primary cultures of rat and murine hippocampal neurons are widely used to reveal cellular mechanisms in neurobiology. By isolating and growing individual ...

Mitochondria-associated ER Membranes (MAMs) and Glycosphingolipid Enriched Microdomains (GEMs): Isolation from Mouse Brain

Intracellular organelles are highly dynamic structures with varying shape and composition, which are subjected to cell-specific intrinsic and extrinsic cues. Their membranes are often juxtaposed at defined contact sites, which become hubs for the exchange of signaling molecules and membrane components1,2,3,4. The inter-organellar membrane microdomains that are formed between the endoplasmic reticulum (ER) and the mitochondria at the opening of the IP3-sensitive Ca2+ channel are known as the mitochondria associated-ER membranes or MAMs4,5,6. The protein/lipid composition and biochemical properties of these membrane contact sites have been extensively studied particularly in relation to their role in regulating intracellular Ca2+ 4,5,6. The ER serves as the primary store of intracellular Ca2+, and in this capacity regulates a myriad of cellular processes downstream of Ca2+ signaling, including post-translational protein folding and protein maturation7. Mitochondria, on the other hand, maintain Ca2+ homeostasis, by buffering cytosolic Ca2+ concentration thereby preventing the initiation of apoptotic pathways downstream of Ca2+ unbalance4,8. The dynamic nature of the MAMs makes them ideal sites to dissect basic cellular mechanisms, including Ca2+ signaling and regulation of mitochondrial Ca2+ concentration, lipid biosynthesis and transport, energy metabolism and cell survival 4,9,10,11,12. Several protocols have been described for the purification of these microdomains from liver tissue and cultured cells13,14. 
	Taking previously published methods into account, we have adapted a protocol for the isolation of mitochondria and MAMs from the adult mouse brain. To this procedure we have added an extra purification step, namely a Triton X100 extraction, which enables the isolation of the glycosphingolipid enriched microdomain (GEM) fraction of the MAMs. These GEM preparations share several protein components with caveolae and lipid rafts, derived from the plasma membrane or other intracellular membranes, and are proposed to function as gathering points for the clustering of receptor proteins and for protein&#x2013;protein interactions4,15.

Mitochondria-associated ER Membranes MAMs and Glycosphingolipid Enriched Microdomains GEMs: Isolation from Mouse Brain

This procedure illustrates how to isolate from the adult mouse brain the mitochondria-associated ER membranes or MAMs and the glycosphingolipid-enriched microdomain fractions from MAMs and mitochondrial preparations.

I mitocondri associati Membrane ER (MAMs) e glicosfingolipidi microdomini arricchiti (GEM): Isolamento dal cervello di topo

Intracellular organelles are highly dynamic structures with varying shape and composition, which are subjected to cell-specific intrinsic and extrinsic ...

Paired Whole Cell Recordings in Organotypic Hippocampal Slices

Pair recordings involve simultaneous whole cell patch clamp recordings from two synaptically connected neurons, enabling not only direct electrophysiological characterization of the synaptic connections between individual neurons, but also pharmacological manipulation of either the presynaptic or the postsynaptic neuron. When carried out in organotypic hippocampal slice cultures, the probability that two neurons are synaptically connected is significantly increased. This preparation readily enables identification of cell types, and the neurons maintain their morphology and properties of synaptic function similar to that in native brain tissue. A major advantage of paired whole cell recordings is the highly precise information it can provide on the properties of synaptic transmission and plasticity that are not possible with other more crude techniques utilizing extracellular axonal stimulation. Paired whole cell recordings are often perceived as too challenging to perform. While there are challenging aspects to this technique, paired recordings can be performed by anyone trained in whole cell patch clamping provided specific hardware and methodological criteria are followed. The probability of attaining synaptically connected paired recordings significantly increases with healthy organotypic slices and stable micromanipulation allowing independent attainment of pre- and postsynaptic whole cell recordings. While CA3-CA3 pyramidal cell pairs are most widely used in the organotypic slice hippocampal preparation, this technique has also been successful in CA3-CA1 pairs and can be adapted to any neurons that are synaptically connected in the same slice preparation. In this manuscript we provide the detailed methodology and requirements for establishing this technique in any laboratory equipped for electrophysiology.

Pair recordings are simultaneous whole cell patch clamp recordings from two synaptically connected neurons, enabling precise electrophysiological and pharmacological characterization of the synapses between individual neurons. Here we describe the detailed methodology and requirements for establishing this technique in organotypic hippocampal slice cultures in any laboratory equipped for electrophysiology.

Associati a cellule intere registrazioni in organotipiche fettine di ippocampo

Pair recordings involve simultaneous whole cell patch clamp recordings from two synaptically connected neurons, enabling not only direct ...

Investigation of Synaptic Tagging/Capture and Cross-capture using Acute Hippocampal Slices from Rodents

Synaptic tagging and capture (STC) and cross-tagging are two important mechanisms at cellular level that explain how synapse-specificity and associativity is achieved in neurons within a specific time frame. These long-term plasticity-related processes are the leading candidate models to study the basis of memory formation and persistence at the cellular level. Both STC and cross-tagging involve two serial processes: (1) setting of the synaptic tag as triggered by a specific pattern of stimulation, and (2) synaptic capture, whereby the synaptic tag interacts with newly synthesized plasticity-related proteins (PRPs). Much of the understanding about the concepts of STC and cross-tagging arises from the studies done in CA1 region of the hippocampus and because of the technical complexity many of the laboratories are still unable to study these processes. Experimental conditions for the preparation of hippocampal slices and the recording of stable late-LTP/LTD are extremely important to study synaptic tagging/cross-tagging. This video article describes the experimental procedures to study long-term plasticity processes such as STC and cross-tagging in the CA1 pyramidal neurons using stable, long-term field-potential recordings from acute hippocampal slices of rats.

This video article describes experimental procedures to study long-term plasticity and its associative processes such as synaptic tagging, capture and cross-tagging in the CA1 pyramidal neurons using acute hippocampal slices from rodents.

Indagine di Synaptic Tagging / Cattura e Cross-cattura utilizzando acuta fettine di ippocampo da Roditore

Synaptic tagging and capture (STC) and cross-tagging are two important mechanisms at cellular level that explain how synapse-specificity and associativity ...

Evaluation of Synapse Density in Hippocampal Rodent Brain Slices

In the brain, synapses are specialized junctions between neurons, determining the strength and spread of neuronal signaling. The number of synapses is tightly regulated during development and neuronal maturation. Importantly, deficits in synapse number can lead to cognitive dysfunction. Therefore, the evaluation of synapse number is an integral part of neurobiology. However, as synapses are small and highly compact in the intact brain, the assessment of absolute number is challenging. This protocol describes a method to easily identify and evaluate synapses in hippocampal rodent slices using immunofluorescence microscopy. It includes a three-step procedure to evaluate synapses in high-quality confocal microscopy images by analyzing the co-localization of pre- and postsynaptic proteins in hippocampal slices. It also explains how the analysis is performed and gives representative examples from both excitatory and inhibitory synapses. This protocol provides a solid foundation for the analysis of synapses and can be applied to any research investigating the structure and function of the brain.

A protocol for accurately identifying and analyzing synapses in hippocampal slices using immunofluorescence is outlined in this article.

Valutazione di densità di sinapsi nelle fette Hippocampal del cervello del roditore

In the brain, synapses are specialized junctions between neurons, determining the strength and spread of neuronal signaling. The number of synapses is ...

Implantation of Chronic Silicon Probes and Recording of Hippocampal Place Cells in an Enriched Treadmill Apparatus

An important requisite for understanding brain function is the identification of behavior and cell activity correlates. Silicon probes are advanced electrodes for large-scale electrophysiological recording of neuronal activity, but the procedures for their chronic implantation are still underdeveloped. The activity of hippocampal place cells is known to correlate with an animal&#39;s position in the environment, but the underlying mechanisms are still unclear. To investigate place cells, here we describe a set of techniques which range from the fabrication of devices for chronic silicon probe implants to the monitoring of place field activity in a cue-enriched treadmill apparatus. A micro-drive and a hat are built by fitting and fastening together 3D-printed plastic parts. A silicon probe is mounted on the micro-drive, cleaned, and coated with dye. A first surgery is performed to fix the hat on the skull of a mouse. Small landmarks are fabricated and attached to the belt of a treadmill. The mouse is trained to run head-fixed on the treadmill. A second surgery is performed to implant the silicon probe in the hippocampus, following which broadband electrophysiological signals are recorded. Finally, the silicon probe is recovered and cleaned for reuse. The analysis of place cell activity in the treadmill reveals a diversity of place field mechanisms, outlining the benefit of the approach.

We describe the diverse steps to implant chronic silicon probes and to record place cells in mice that are running head-fixed on a cue-enriched treadmill apparatus.

Impianto di silicio cronica sonde e registrazione delle cellule ippocampali posto in un apparato di tapis roulant arricchito

An important requisite for understanding brain function is the identification of behavior and cell activity correlates. Silicon probes are advanced ...

An Improved Method for Collection of Cerebrospinal Fluid from Anesthetized Mice

The cerebrospinal fluid (CSF) is a valuable body fluid for analysis in neuroscience research. It is one of the fluids in closest contact with the central nervous system and thus, can be used to analyze the diseased state of the brain or spinal cord without directly accessing these tissues. However, in mice it is difficult to obtain from the cisterna magna due to its closeness to blood vessels, which often contaminate samples. The area for CSF collection in mice is also difficult to dissect to and often only small samples are obtained (maximum of 5-7 &#181;L or less). This protocol describes in detail a technique that improves on current methods of collection to minimize contamination from blood and allow for the abundant collection of CSF (on average 10-15 &#181;L can be collected). This technique can be used with other dissection methods for tissue collection from mice, as it does not impact any tissues during CSF extraction. Thus, the brain and spinal cord are not affected with this technique and remain intact. With greater CSF sample collection and purity, more analyses can be used with this fluid to further aid neuroscience research and better understand diseases affecting the brain and spinal cord.

This protocol describes an improved technique for the abundant collection of cerebrospinal fluid (CSF) with no contamination from blood. With greater sample collection and purity, more analyses can be performed using CSF to further our understanding of diseases that affect the brain and spinal cord.

Un metodo migliore per la raccolta di liquido cerebrospinale da topi anestetizzati

The cerebrospinal fluid (CSF) is a valuable body fluid for analysis in neuroscience research. It is one of the fluids in closest contact with the central ...

Preparation of Acute Human Hippocampal Slices for Electrophysiological Recordings

Epilepsy affects about 1% of the world population and leads to a severe decrease in quality of life due to ongoing seizures as well as high risk for sudden death. Despite an abundance of available treatment options, about 30% of patients are drug-resistant. Several novel therapeutics have been developed using animal models, though the rate of drug-resistant patients remains unaltered. One of probable reasons is the lack of translation between rodent models and humans, such as a weak representation of human pharmacoresistance in animal models. Resected human brain tissue as a preclinical evaluation tool has the advantage to bridge this translational gap. Described here is a method for high quality preparation of human hippocampal brain slices and subsequent stable induction of epileptiform activity. The protocol describes the induction of burst activity during application of 8 mM KCl and 4-aminopyridin. This activity is sensitive to established AED lacosamide or novel antiepileptic candidates, such as dimethylethanolamine (DMEA). In addition, the method describes induction of seizure-like events in CA1 of human hippocampal brain slices by reduction of extracellular Mg2+ and application of bicuculline, a GABAA receptor blocker. The experimental set-up can be used to screen potential antiepileptic substances for their effects on epileptiform activity. Furthermore, mechanisms of action postulated for specific compounds can be validated using this approach in human tissue (e.g., using patch-clamp recordings). To conclude, investigation of vital human brain tissue ex vivo (here, resected hippocampus from patients suffering from temporal lobe epilepsy) will improve the current knowledge of physiological and pathological mechanisms in the human brain.

The presented protocol describes the transport and preparation of resected human hippocampal tissue with the ultimate goal to use vital brain slices as a preclinical evaluation tool for potential antiepileptic substances.

Preparazione di fette acute di ippocampale umano per registrazioni elettrofisiologiche

Epilepsy affects about 1% of the world population and leads to a severe decrease in quality of life due to ongoing seizures as well as high risk for ...

Isolamento di CA1 nucleari arricchiti Frazioni di fettine di ippocampo per studiare l'attività-dipendente nucleare Importazione di Messenger proteine ​​Synapto-nucleari

Isolamento di CA1 nucleari arricchiti Frazioni di fettine di ippocampo per studiare l'attività-dipendente nucleare Importazione di Messenger proteine Synapto-nucleari