Die Autoren bedanken sich bei Ikiel Ptito für seine weitere fachliche Unterstützung danken. NSERC Zuschuss zu MP.

Teil 1: Pre-Processing von Gewebe <ol><li> Tissue sollte gut mit Paraformaldehyd, Glutaraldehyd oder Formalin perfundiert werden. Dies kann durch Standard-transcardial Perfusion in der Regel verwendet, um andere Organe Ernte erreicht werden. In der vorliegenden Studie das Thema war tief mit Ketaminhydrochlorid (10 mg / kg, im), mit einer Überdosis Natrium-Pentobarbital (25 mg / kg, iv) eingeschläfert sediert und perfundierten transkardial mit 0,1 M PBS, bis sie vollständig exsanguinated.This folgt von einem 4% Paraformaldehyd-Lösung in PBS für 5 min (~ 1 Liter). </li></ol> Teil 2: Stereotaktische blockiert <ol><li> Vor Inbetriebnahme des Kopfes in den stereotaktischen Rahmen der Koordinaten des Horsley-Clarke/interaural Flugzeug Null muss genommen werden. Dies ist die theoretische Mitte zwischen den Ohren. Zur Messung dieser Ebene, das Ohr Bars gleichermaßen in das Gerät eingebaut werden müssen, legen Sie dann ein Skalpell in der stereotaktischen Manipulatorarm und messen in der Mitte zwischen dem Ohr Bars. Dies ist für die Bestimmung, wo das Gewebe auf die Forschung Bedürfnisse Block wichtig. Sobald dies abgeschlossen ist der Schädel muss für die Fixierung in den stereotaktischen Apparat vorbereitet werden. </li><li> Um den Kopf in den stereotaktischen Rahmen statt des Unterkiefers wird sich mit Knochen Rongeure und einem Skalpell entfernt werden. Zusätzlich wird die Haut-, Muskel-und Bindegewebe sollte entfernt werden, um den Schädel freizulegen. Sobald das Bindegewebe aus dem Schädel entfernt wird, setzen das Gehirn durch kratzen die Schädeldecke (der tabellarischen Teil des Os occipitale sowie die parietal, ad Stirnbeins). In dem vorliegenden Experiment Teil der Schädeldecke ist alles fertig wurde entfernt. Achten Sie darauf, nicht vollständig zu entfernen zeitlichen Knochen, da die Gehörgänge müssen intakt sein, den Kopf in den stereotaktischen Rahmen statt. Die restlichen dura Angelegenheit sollte von den freiliegenden Gehirns entfernt werden. Der Schädel ist nun bereit, in den stereotaktischen Rahmen platziert werden. </li><li> In der gleichen Weise, in der man einen stereotaktischen Operation durchführen würde, passen Sie die Augen, Gaumen und Ohr Bars, so dass der Kopf sicher in der stereotaktischen Apparat fixiert. Setzen Sie den stereotaktischen Manipulators in der vorgegebenen anterior / posterior (A / P) koordiniert und bewegen Sie den Manipulator der lateralen Seite des Gehirns. Langsam senken die Klinge in das Gehirn, völlig erhöhen die Klinge aus dem Gehirn, dann medial bewegen und senken Sie die Klinge wieder. Wiederholen Sie diese beiden Schritte, bis die Klinge der lateralen Seite der gegenüberliegenden Hemisphäre erreicht hat. Damit ist die erste koronalen blockieren. Für die anschließende koronale Blöcke verschieben Sie den Manipulator 1cm in die A / P-Achse, und wiederholen Sie, bis das gesamte Gehirn blockiert wurde. </li></ol> Teil 3: Entfernen der Gehirn aus dem Schädel <ol><li> Entfernen Sie den Kopf aus dem stereotaktischen Rahmen und halten Sie die freiliegende Gehirn in der Handfläche. Versuchen Sie, das Gehirn durch leichtes Platzierung Verweichlichung des Gehirns in der Handfläche und platzieren Sie Ihre kleinen Finger über den Frontallappen, dies minimiert Bewegung des Gehirns in den Schädel zu sichern. Um die Trocknung der pialen Oberfläche des Gehirns zu verhindern, legen Sie ein Stück PBS angefeuchteten Mull über das Gehirn. Halten Sie den Kopf fest mit dem Schädel und Chip entfernt die restlichen occipital und zeitlichen Knochen zusammen mit der Wirbelsäule. Dies macht die Basis und seitliche Aspekte des Gehirns. Schließlich entfernen Sie alle verbleibenden Stirnbein und das Nasenbein, die Zugang zu den Riechkolben ermöglichen. Es ist wichtig, das Stirnbein letzten entfernen, weil, wie Sie die Basis des Schädels entfernt das Gehirn bewegt sich leicht und die Frontallappen auf die gezackten Ränder der Fontal Knochen beschädigt werden. Cut entfernt und noch verbleibende Dauer Angelegenheit. Heben Sie die Vorderseite des Gehirns, schieben Sie das Skalpell unter dem Gehirn und kostenlos das Gehirn aus dem Schädel. </li></ol> Teil 4: Messungen <ol><li> Es gibt eine Reihe von nützlichen Messungen, die vor dem Einfrieren gemacht werden können. Zum Beispiel die A / P-Achse des Gehirns mit einer Schieblehre. Darüber hinaus die spezifische Dichte kann durch Wiegen des Gehirns gemessen werden, Messvolumen durch die Verdrängung von Wasser in einem Messzylinder dividiert Raumgewicht Verschiebung (Tabelle 1). </li></ol> Teil 5: Fertig blockiert das Gehirn. <ol><li> Normalerweise, wenn das Skalpell in das Gehirn eingeführt wird es nicht lange genug, um vollständig durchdringen die volle dorsal-ventralen Umfang des Gehirns. Sobald das Gehirn entfernt und grobe Messungen erhalten, nehmen Sie eine Gewebe-Schneidscheibe und Ziel blockiert das Gehirn durch die Bauchseite des Gehirns (Abbildung 2). </li><li> Vor dem Einfrieren der Blöcke, ist es notwendig, das Gewebe in abgestuften PBS-gepufferte Saccharose-Lösungen cryoprotect (10, 20 und 30%) gehalten bei 4 ˚ C, bis das Gehirn sinkt. Es dauert in der Regel einer Inkubation über Nacht in 10%, 2-3 Tage in 20% und weitere 3-5 Tage in 30% für die Blöcke an den Boden des Behälters sinken. Ein täglicher Wechsel der the 30% Saccharose-Lösung wird empfohlen. </li></ol> Teil 6: Repräsentative Ergebnisse Es gibt eine Reihe von groben morphologischen Messungen, die vorgenommen werden, wenn das Gehirn aus dem Schädel entfernt worden sein kann. Dazu gehören A / P Länge, Gewicht und spezifische Dichte (Tabelle 1). Wir in der Regel blockieren das Gehirn in 6-7 Blöcke messen 1cm (Abbildung 1). Jedes Stück wird dann fotografiert (Abbildung 2) und kann weiter je nach Forschungsbedarf zerlegt werden oder hergerichtet für das Einfrieren in abgestuften Saccharose-Lösungen. <table border="1"><tbody><tr><td> Thema </td><td> A / P Länge (Mm) </td><td> Gewicht (G) </td><td> Wasserverdrängung (Ml) </td><td> Spezifische Dichte (G / ml) </td></tr><tr><td> O2303-2-1-1 </td><td> 64,3 </td><td> 28,1 </td><td> 24 </td><td> 1,171 </td></tr><tr><td> O5180-1 </td><td> 71,3 </td><td> 38,7 </td><td> 34 </td><td> 1,138 </td></tr><tr><td> O2708-3-1 </td><td> 62,8 </td><td> 28,7 </td><td> 26 </td><td> 1,104 </td></tr><tr><td> O9184-4-2 </td><td> 65,3 </td><td> 29,5 </td><td> 24 </td><td> 1,229 </td></tr><tr><td> N459-1-14-2 </td><td> 68,2 </td><td> 31,6 </td><td> 26 </td><td> 1,215 </td></tr><tr><td> AVERAGE </td><td> 66,38 </td><td> 31,32 </td><td> 26,8 </td><td> 1,171 </td></tr><tr><td> STD DEV </td><td> 3,38 </td><td> 4,33 </td><td> 4,17 </td><td> 0,052 </td></tr></tbody></table> Tabelle 1. Gross Morphologische Messungen der Right Hemisphere von 5 Monate alten Meerkatzen <img src="/files/ftp_upload/1259/1259fig1.jpg" alt="Abbildung 1" /> <img src="/files/ftp_upload/1259/1259fig2.jpg" alt="Abbildung 1.5" /> Abbildung 1. Schaltpläne für die Frontalebene zur Blockierung des Gehirns eingesetzt. Dies ist ein Beispiel für eine externalisiert Erwachsenen vervet Gehirn. Beispiel für die Sperrung Verfahren. Die vertikalen Linien sind hier bei 1cm Abstand, typischerweise Herstellung von 7 koronalen Blocks von jeder Hemisphäre. <img src="/files/ftp_upload/1259/1259fig3.jpg" alt="Abbildung 2" /> Abbildung 2. Blockiert von Hirngewebe in stereotaktischen Raum. Jeder Block wird Ausbeute etwa 200 Sektionen 50 um übernommen. Mit diesem Stichprobenverfahren über 1200 Schnitte durch die Rinde wird genommen, und eine zusätzliche 400-500 aus dem Kleinhirn, wenn in der koronalen Ebene geschnitten.

<ol>
	<li>Gallagher, M., Rapp, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+animal+models+to+study+the+effects+of+aging+on+cognition.+Annu+Rev+Psychol+48.">The use of animal models to study the effects of aging on cognition. Annu Rev Psychol 48.</a> , 339-370 (1997).</li><li>Clancy, B., Darlington, R., Finlay, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Translating+developmental+time+across+mammalian+species.">Translating developmental time across mammalian species.</a> Neuroscience. 105, 7-17 (2001).</li><li>Nowakowski, R. S., Rakic, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+site+of+origin+and+route+and+rate+of+migration+of+neurons+to+the+hippocampal+region+of+the+rhesus+monkey.">The site of origin and route and rate of migration of neurons to the hippocampal region of the rhesus monkey.</a> J Comp Neurol. 196, 129-154 (1981).</li><li>Rakic, P., Bourgeois, J. P., Eckenhoff, M. F., Zecevic, N., Goldman-Rakic, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Concurrent+overproduction+of+synapses+in+diverse+regions+of+the+primate+cerebral+cortex.">Concurrent overproduction of synapses in diverse regions of the primate cerebral cortex.</a> Science. 232, 232-235 (1986).</li><li>Granger, B., Tekaia, F., Le Sourd, A. M., Rakic, P., Bourgeois, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tempo+of+neurogenesis+and+synaptogenesis+in+the+primate+cingulate+mesocortex:+comparison+with+the+neocortex.">Tempo of neurogenesis and synaptogenesis in the primate cingulate mesocortex: comparison with the neocortex.</a> J Comp Neurol. 360, 363-376 (1995).</li><li>Zecevic, N., Rakic, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+layer+I+neurons+in+the+primate+cerebral+cortex.">Development of layer I neurons in the primate cerebral cortex.</a> J Neurosci. 21, 5607-5619 (2001).</li><li>Ervin, F. R., Palmour, R. M., Young, S. N., Guzman-Flores, C., Juarez, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Voluntary+consumption+of+beverage+alcohol+by+vervet+monkeys:+population+screening,+descriptive+behavior+and+biochemical+measures.">Voluntary consumption of beverage alcohol by vervet monkeys: population screening, descriptive behavior and biochemical measures.</a> Pharmacol Biochem Behav. 36, 367-373 (1990).</li><li>Palmour, R. M., Mulligan, J., Howbert, J. J., Ervin, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Of+monkeys+and+men:+vervets+and+the+genetics+of+human-like+behaviors.">Of monkeys and men: vervets and the genetics of human-like behaviors.</a> Am J Hum Genet. 61, 481-488 (1997).</li><li>Boire, D., Th&#233;oret, H., Ptito, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereological+evaluation+of+neurons+and+glia+in+the+monkey+dorsal+lateral+geniculate+nucleus+following+an+early+cerebral+hemispherectomy.">Stereological evaluation of neurons and glia in the monkey dorsal lateral geniculate nucleus following an early cerebral hemispherectomy.</a> Exp Brain Res. 142, 208-220 (2002).</li><li>Bjugstad, K. B., Teng, Y. D., Redmond, D. E. J. r., Elsworth, J. D., Roth, R. H., Cornelius, S. K., Snyder, E. Y., Sladek, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+neural+stem+cells+migrate+along+the+nigrostriatal+pathway+in+a+primate+model+of+Parkinson's+disease.">Human neural stem cells migrate along the nigrostriatal pathway in a primate model of Parkinson's disease.</a> Exp Neurol. 211, 362-369 (2008).</li><li>Lemere, C. A., Beierschmitt, A., Iglesias, M., Spooner, E. T., Bloom, J. K., Leverone, J. F., Zheng, J. B., Seabrook, T. J., Louard, D., Li, D., Selkoe, D. J., Palmour, R. M., Ervin, F. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alzheimer's+disease+abeta+vaccine+reduces+central+nervous+system+abeta+levels+in+a+non-human+primate,+the+Caribbean+vervet.">Alzheimer's disease abeta vaccine reduces central nervous system abeta levels in a non-human primate, the Caribbean vervet.</a> Am J Pathol. 165, 283-297 (2004).</li><li>Mash, D. C., Staley, J. K., Doepel, F. M., Young, S. N., Ervin, F. R., Palmour, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Altered+dopamine+transporter+densities+in+alcohol-preferring+vervet+monkeys.">Altered dopamine transporter densities in alcohol-preferring vervet monkeys.</a> Neuroreport. 7, 457-462 (1996).</li><li>Burke, M. W., Palmour, R. M., Ervin, F. R., Ptito, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuronal+reduction+in+frontal+cortex+of+primates+after+prenatal+alcohol+exposure.">Neuronal reduction in frontal cortex of primates after prenatal alcohol exposure.</a> Neuroreport. 20, 13-17 (2009).</li></ol>

The authors have nothing to disclose.

Die St. Kitts vervet (Chlorocebus aethiops sabeus) ist ein Old World Primaten mit ähnlichen Mustern und Preisen von kortikalen und subkortikalen die Entwicklung des Gehirns wie das des Menschen. Diese Spezies wurde verwendet, um komplexe menschliche Verhaltensstörungen wie ängstliches Verhalten, Bluthochdruck 8, Hemisphärektomie 9, Parkinson-Krankheit 10, Alzhemier-Krankheit 11, und Alkoholmissbrauch 12 Modell. In jüngerer Zeit hat diese Art verwendet ...

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<td>Scalpel</td>
<td>&nbsp;</td>
<td>Fine Science Tools</td>
<td>10003-12</td>
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<td>Scalpel blades</td>
<td>&nbsp;</td>
<td>Fine Science Tools</td>
<td>10011-00</td>
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<td>Fine Science Tools</td>
<td>14090-11</td>
<td>Any surgical scissors are sufficient</td>
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<td>Rongeurs</td>
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<td>Fine Science Tools</td>
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dissecting the non-human primate brain in stereotaxic space

Die Verwendung von nicht-menschlichen Primaten bietet eine hervorragende translationale Modell für unser Verständnis der Entwicklungs-und Alterungsprozessen beim Menschen<sup&gt; 1-6</sup&gt;. Darüber hinaus hat die Verwendung von nicht-menschlichen Primaten vor kurzem die Gelegenheit geboten, natürlich Modellierung komplexer psychiatrischer Störungen wie Alkoholmissbrauch<sup&gt; 7</sup&gt;. Hier beschreiben wir eine Technik für die Sperrung des Gehirns in der koronalen Ebene der grünen Meerkatze (<em&gt; Chlorocebus aethiops sabeus</em&gt;) In die intakte Schädeldecke in stereotaktischen Raum. Die hier beschriebene Methode bietet einen Standard Schnittfläche zwischen den Blöcken und Themen und minimiert Teilstrecken zwischen den Blöcken. Schnitte eines Blocks von Gewebe in der koronalen Ebene erleichtert auch die Abgrenzung eines Gebiets von Interesse. Diese Methode bietet überschaubar großen Blöcken, da eine einzelne Hemisphäre des grünen Meerkatze liefert mehr als 1200 Teile beim Schneiden bei 50 um. Außerdem blockiert das Gehirn in 1 cm-Blöcke, erleichtert es das Eindringen von Saccharose cyroprotection und ermöglicht den Block auf einem Standard-Kryostat geschnitten werden.

Watch this Scientific Journal Video about Dissecting the Non-human Primate Brain in Stereotaxic Space at JoVE.com

Dissecting the Non-human Primate Brain in Stereotaxic Space

Die nicht-menschlichen Primaten ist ein wichtiger translationale Arten für unser Verständnis der normalen Verarbeitung des Gehirns. Die anatomische Organisation des Primas Gehirn kann wichtige Einblicke in normalen und pathologischen Bedingungen beim Menschen liefern.

Grundlagen zur nicht-menschlichen Primaten Brain in stereotaktischen Raum

The use of non-human primates provides an excellent translational model for our understanding of developmental and aging processes in humans1-6. In ...

dissecting-the-non-human-primate-brain-in-stereotaxic-space

Research

JoVE Journal

Biology

10.0K Aufrufe.  University of Montreal. Die nicht-menschlichen Primaten ist ein wichtiger translationale Arten für unser Verständnis der normalen Verarbeitung des Gehirns. Die anatomische Organisation des Primas Gehirn kann wichtige Einblicke in normalen und pathologischen Bedingungen beim Menschen liefern.

Serie: Dissecting the Non-human Primate Brain in Stereotaxic Space

Single Cell Electroporation in vivo within the Intact Developing Brain

Single-cell electroporation (SCE) is a specialized technique allowing the delivery of DNA or other macromolecules into individual cells within intact tissue, including in vivo preparations. The distinct advantage of this technique is that experimental manipulations may be performed on individual cells while leaving the surrounding tissue unaltered, thereby distinguishing cell-autonomous effects from those resulting from global treatments. When combined with advanced in vivo imaging techniques, SCE of fluorescent markers permits direct visualization of cellular morphology, cell growth, and intracellular events over timescales ranging from seconds to days. While this technique is used in a variety of in vivo and ex vivo preparations, we have optimized this technique for use in Xenopus laevis tadpoles. In this video article, we detail the procedure for SCE of a fluorescent dye or plasmid DNA into neurons within the intact brain of the albino Xenopus tadpole. We also discuss methods to optimize yield, and show examples of live two-photon fluorescence imaging of neurons fluorescently labeled by SCE.

Single-cell electroporation (SCE) is a specialized technique allowing delivery of DNA or other macromolecules into individual cells within intact tissue, including in vivo preparations. Here we detail the procedure for SCE of a fluorescent dye or plasmid DNA into neurons within the intact brain of the Xenopus laevis tadpole.

Single Cell Elektroporation in vivo innerhalb der intakten sich entwickelnde Gehirn

Single-cell electroporation (SCE) is a specialized technique allowing the delivery of DNA or other macromolecules into individual cells within intact ...

Forschung

Biologie

Survivable Stereotaxic Surgery in Rodents 

The ability to measure extracellular basal levels of neurotransmitters in the brain of awake animals allows for the determination of effects of different systemic challenges (pharmacological or physiological) to the CNS. For example, one can directly measure how the animal's midbrain dopamine projections respond to dopamine-releasing drugs like d-amphetamine or natural stimuli like food. In this video, we show you how to implant guide cannulas targeting specific sites in the rat brain, how to insert and implant a microdialysis probe and how to use high performance liquid chromatography coupled with electrochemical detection (HPLC-EC) to measure extracellular levels of oxidizable neurotransmitters and metabolites. Local precise introduction of drugs through the microdialysis probe allows for refined work on site specificity in a compound s mechanism of action. This technique has excellent anatomical and chemical resolution but only modest time resolution as microdialysis samples are usually processed every 20-30 minutes to ensure detectable neurotransmitter levels. Complementary ex vivo tools (i.e., slice and cell culture electrophysiology) can assist with monitoring real-time neurotransmission.

Survivable Stereotaxic Surgery in Rodents

The monitoring of extracellular neurotransmitter levels in distinct brain regions of freely moving animals offers insights on the link between neurotransmitter release and behavior. In vivo microdialysis coupled with electrochemical detection provides excellent anatomical and chemical resolution; and information on how basal neurotransmission is altered by pharmacological or physiological manipulations.

Survivable stereotaktischen Chirurgie in Nagetiere

The ability to measure extracellular basal levels of neurotransmitters in the brain of awake animals allows for the determination of effects of different ...

Dissecting and Recording from The C. Elegans Neuromuscular Junction

Neurotransmission is the process by which neurons transfer information via chemical signals to their post-synaptic targets, on a rapid time scale. This complex process requires the coordinated activity of many pre- and post-synaptic proteins to ensure appropriate synaptic connectivity, conduction of electrical signals, targeting and priming of secretory vesicles, calcium sensing, vesicle fusion, localization and function of postsynaptic receptors and finally, recycling mechanisms. As neuroscientists it is our goal to elucidate which proteins function in each of these steps and understand their mechanisms of action. Electrophysiological recordings from synapses provide a quantifiable read out of the underlying electrical events that occur during synaptic transmission. By combining this technique with the powerful array of molecular and genetic tools available to manipulate synaptic proteins in C. elegans, we can analyze the resulting functional changes in synaptic transmission. 
The C. elegans NMJs formed between motor neurons and body wall muscles control locomotion, therefore, mutants with uncoordinated locomotory phenotypes (known as unc s) often perturb synaptic transmission at these synapses 1. Since unc mutants are maintained on a rich supply of a bacterial food source, they remain viable as long as they retain some pharyngeal pumping ability to ingest food. This, together with the fact that C. elegans exist as hermaphrodites, allows them to pass on mutant progeny without the need for elaborate mating behaviors. These attributes, coupled with our recent ability to record from the worms NMJs 2,3,7 make this an excellent model organism in which to address precisely how unc mutants impact neurotransmission. 
The dissection method involves immobilizing adult worms using a cyanoacrylic glue in order to make an incision in the worm cuticle exposing the NMJs. Since C. elegans adults are only 1 mm in length the dissection is performed with the use of a dissecting microscope and requires excellent hand-eye coordination. NMJ recordings are made by whole-cell voltage clamping individual body wall muscle cells and neurotransmitter release can be evoked using a variety of stimulation protocols including electrical stimulation, light-activated channel-rhodopsin-mediated depolarization 4 and hyperosmotic saline, all of which will be briefly described.

Application of electrophysiology to accessible synapses provides a quantifiable measure of synaptic activity, useful in analyzing synaptic mutants. This article describes a dissection method used to expose the neuromuscular junctions (NMJ) of Caenorhabditis elegans (C. elegans) and briefly discusses some of the uses to which this preparation can be applied.

Dissecting und Aufnahme von C. elegans neuromuskulären Synapse

Neurotransmission is the process by which neurons transfer information via chemical signals to their post-synaptic targets, on a rapid time scale.   This ...

The Gateway to the Brain: Dissecting the Primate Eye

The visual system in humans is considered the gateway to the world and plays a principal role in the plethora of sensory, perceptual and cognitive processes. It is therefore not surprising that quality of vision is tied to quality of life . Despite widespread clinical and basic research surrounding the causes of visual disorders, many forms of visual impairments, such as retinitis pigmentosa and macular degeneration, lack effective treatments. Non-human primates have the closest general features of eye development to that of humans. Not only do they have a similar vascular anatomy, but amongst other mammals, primates have the unique characteristic of having a region in the temporal retina specialized for high visual acuity, the fovea1. Here we describe a general technique for dissecting the primate retina to provide tissue for retinal histology, immunohistochemistry, laser capture microdissection, as well as light and electron microscopy. With the extended use of the non-human primate as a translational model, our hope is that improved understanding of the retina will provide insights into effective approaches towards attenuating or reversing the negative impact of visual disorders on the quality of life of affected individuals.

The non-human primate is an important translational species for our understanding of development and aging. The anatomical organization of the primate retina may provide important insights into normal and pathological conditions in humans.

Das Tor zum Gehirn: Die Biologie des Primas Eye

The visual system in humans is considered the  gateway  to the world and plays a principal role in the plethora of sensory, perceptual and cognitive ...

Knowing What Counts: Unbiased Stereology in the Non-human Primate Brain

The non-human primate is an important translational species for understanding the normal function and disease processes of the human brain. Unbiased stereology, the method accepted as state-of-the-art for quantification of biological objects in tissue sections2, generates reliable structural data for biological features in the mammalian brain3. The key components of the approach are unbiased (systematic-random) sampling of anatomically defined structures (reference spaces), combined with quantification of cell numbers and size, fiber and capillary lengths, surface areas, regional volumes and spatial distributions of biological objects within the reference space4. Among the advantages of these stereological approaches over previous methods is the avoidance of all known sources of systematic (non-random) error arising from faulty assumptions and non-verifiable models. This study documents a biological application of computerized stereology to estimate the total neuronal population in the frontal cortex of the vervet monkey brain (Chlorocebus aethiops sabeus), with assistance from two commercially available stereology programs, BioQuant Life Sciences and Stereologer (Figure 1). In addition to contrast and comparison of results from both the BioQuant and Stereologer systems, this study provides a detailed protocol for the Stereologer system.

The anatomical organization of the primate brain can provide important insights into normal and pathological conditions in humans. Unbiased stereology is a method for accurately and efficiently estimating the total neuron number (or other cell type) in a given reference space1.

Zu wissen, was zählt: Unbiased Stereology in der nicht-menschlichen Primaten Gehirn

The non-human primate is an important translational species for understanding the normal function and disease processes of the human brain. Unbiased ...

Trajectory Data Analyses for Pedestrian Space-time Activity Study

It is well recognized that human movement in the spatial and temporal dimensions has direct influence on disease transmission1-3. An infectious disease typically spreads via contact between infected and susceptible individuals in their overlapped activity spaces. Therefore, daily mobility-activity information can be used as an indicator to measure exposures to risk factors of infection. However, a major difficulty and thus the reason for paucity of studies of infectious disease transmission at the micro scale arise from the lack of detailed individual mobility data. Previously in transportation and tourism research detailed space-time activity data often relied on the time-space diary technique, which requires subjects to actively record their activities in time and space. This is highly demanding for the participants and collaboration from the participants greatly affects the quality of data4.
Modern technologies such as GPS and mobile communications have made possible the automatic collection of trajectory data. The data collected, however, is not ideal for modeling human space-time activities, limited by the accuracies of existing devices. There is also no readily available tool for efficient processing of the data for human behavior study. We present here a suite of methods and an integrated ArcGIS desktop-based visual interface for the pre-processing and spatiotemporal analyses of trajectory data. We provide examples of how such processing may be used to model human space-time activities, especially with error-rich pedestrian trajectory data, that could be useful in public health studies such as infectious disease transmission modeling.
The procedure presented includes pre-processing, trajectory segmentation, activity space characterization, density estimation and visualization, and a few other exploratory analysis methods. Pre-processing is the cleaning of noisy raw trajectory data. We introduce an interactive visual pre-processing interface as well as an automatic module. Trajectory segmentation5 involves the identification of indoor and outdoor parts from pre-processed space-time tracks. Again, both interactive visual segmentation and automatic segmentation are supported. Segmented space-time tracks are then analyzed to derive characteristics of one's activity space such as activity radius etc. Density estimation and visualization are used to examine large amount of trajectory data to model hot spots and interactions. We demonstrate both density surface mapping6 and density volume rendering7. We also include a couple of other exploratory data analyses (EDA) and visualizations tools, such as Google Earth animation support and connection analysis. The suite of analytical as well as visual methods presented in this paper may be applied to any trajectory data for space-time activity studies.

A suite of spatiotemporal processing methods are presented to analyze human trajectory data, such as that collected using a GPS device, for the purpose of modeling pedestrian space-time activities.

Bahndaten Analysen für Fußgänger Raum-Zeit-Activity Study

It is well recognized that human movement in the  spatial and temporal dimensions has direct influence on disease transmission1-3.  An infectious disease ...

Physiology Lab Demonstration: Glomerular Filtration Rate in a Rat

Measurements of glomerular filtration rate (GFR), and the fractional excretion of sodium (Na) and potassium (K) are critical in assessing renal function in health and disease. GFR is measured as the steady state renal clearance of inulin which is filtered at the glomerulus, but not secreted or reabsorbed along the nephron. The fractional excretion of Na and K can be determined from the concentration of Na and K in plasma and urine. The renal clearance of inulin can be demonstrated in an anesthetized animal which has catheters in the femoral artery, femoral vein and bladder. The equipment and supplies used for this procedure are those commonly available in a research core facility, and thus makes this procedure a practical means for measuring renal function. The purpose of this video is to demonstrate the procedures required to perform a lab demonstration in which renal function is assessed before and after a diuretic drug. The presented technique can be utilized to assess renal function in rat models of renal disease.

The purpose of this protocol is to demonstrate the principles and techniques for measuring and calculating glomerular filtration rate, urine flow rate, and excretion of sodium and potassium in a rat. This demonstration can be used to provide students with an overall conceptual understanding of how to measure renal function.

Physiology Lab Demonstration: glomeruläre Filtrationsrate in einem Ratten-

Measurements of glomerular filtration rate (GFR), and the fractional excretion of sodium (Na) and potassium (K) are critical in assessing renal function ...

Sampling Blood from the Lateral Tail Vein of the Rat

Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, proteins, and glucose, yet the composition of the blood is dynamically regulated and easily perturbed. One factor that can change the blood composition is the stress response triggered by the sampling procedure, which can contribute to variability in the measures of interest. Here we describe a procedure for blood sampling from the lateral tail vein in the rat. This procedure offers significant advantages over other more commonly used techniques. It permits rapid sampling with minimal pain or invasiveness, without anesthesia or analgesia. Additionally, it can be used to obtain large volume samples (upwards of 1 ml in some rats), and it may be used repeatedly across experimental days. By minimizing the stress response and pain resulting from blood sampling, measures can more accurately reflect the true basal state of the animal, with minimal influence from the sampling procedure itself.

Blood samples are useful for assessing biomarkers of physiological states or disease in vivo. Here we describe the methodology to sample blood from the lateral tail vein in the rat. This method provides rapid samples with minimal pain and invasiveness.

Blutprobenentnahme aus der laterale Schwanzvene der Ratte

Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, ...

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.

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.

Mikropunktion Bowmans Platz bei Mäusen durch die 2-Photonen-Mikroskopie

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

Reverse Dissection and DiceCT Reveal Otherwise Hidden Data in the Evolution of the Primate Face

Facial expressions, or facial displays, of social or emotional intent are produced by many mammalian taxa as a means of visually communicating with conspecifics at a close range. These displays are achieved by contraction of the mimetic muscles, which are skeletal muscle attached to the dermis of the face. Reverse dissection, removing the full facial mask from the skull and approaching mimetic muscles in reverse, is an effective but destructive way of revealing the morphology of mimetic muscles but it is destructive. DiceCT is a novel mechanism for visualizing skeletal muscles, including mimetic muscles, and isolating individual muscle fascicles for quantitative measurement. Additionally, DiceCT provides a non-destructive mechanism for visualizing muscles. The combined techniques of reverse dissection and DiceCT can be used to assess the evolutionary morphology of mimetic musculature as well as potential contraction strength and velocity in these muscles. This study further demonstrates that DiceCT can be used to accurately and reliably visualize mimetic muscles as well as reverse dissection and provide a non-destructive method for sampling mimetic muscles.

Facial expressions are a mode of visual communication produced by mimetic muscles. Here, we present protocols for the novel techniques of reverse dissection and DiceCT to fully visualize and assess mimetic muscles. These combined techniques can examine both morphological and physiological aspects of mimetic musculature to determine functional aspects.

Reverse-Dissektion und DiceCT offenbaren sonst versteckt Daten in der Evolution der Primaten-Gesicht

Facial expressions, or facial displays, of social or emotional intent are produced by many mammalian taxa as a means of visually communicating with ...