Les auteurs tiens à remercier premier cycle Daniel Korus pour son aide à l’exécution du code Matlab et premier cycle Alex Boettcher pour son aide en exécutant les expériences comportementales. Ce projet est soutenu par NSF IOS 1256799 à R.L.M. et par le National Institute on Drug Abuse de la National Institutes of Health, sous attribution numéro T32DA007234.

<ol>
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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+measurement+of+glutamate+release+in+the+brain+using+a+dual+enzyme-based+electrochemical+sensor.">Direct measurement of glutamate release in the brain using a dual enzyme-based electrochemical sensor.</a> Brain Res. 659 (1-2), 117-125 (1994).</li><li>Agnesi, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wireless+instantaneous+neurotransmitter+concentration+system-based+amperometric+detection+of+dopamine,+adenosine,+and+glutamate+for+intraoperative+neurochemical+monitoring.">Wireless instantaneous neurotransmitter concentration system-based amperometric detection of dopamine, adenosine, and glutamate for intraoperative neurochemical monitoring.</a> J Neurosurg. 111 (4), 701-711 (2009).</li><li>Erksine, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solicitation+behavior+in+the+estrous+female+rat:+A+review.">Solicitation behavior in the estrous female rat: A review.</a> Horm Beh. 23 (4), 473-502 (1989).</li><li>Weiner, I., Gal, G., Rawlins, J. N., Feldon, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+involvement+of+the+shell+and+core+subterritories+of+the+nucleus+accumbens+in+latent+inhibition+and+amphetamine-induced+activity.">Differential involvement of the shell and core subterritories of the nucleus accumbens in latent inhibition and amphetamine-induced activity.</a> Behav Brain Res. 81 (1-2), 123-133 (1996).</li><li>Heidbreder, C., Feldon, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphetamine-induced+neurochemical+and+locomotor+responses+are+expressed+differentially+across+the+anteroposterior+axis+of+the+core+and+shell+subterritories+of+the+nucleus+accumbens.">Amphetamine-induced neurochemical and locomotor responses are expressed differentially across the anteroposterior axis of the core and shell subterritories of the nucleus accumbens.</a> Synapse. 29 (4), 310-322 (1998).</li><li>Pierce, R. C., Kalivas, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphetamine+produces+sensitized+increases+in+locomotion+and+extracellular+dopamine+preferentially+in+the+nucleus+accumbens+shell+of+rats+administered+repeated+cocaine.">Amphetamine produces sensitized increases in locomotion and extracellular dopamine preferentially in the nucleus accumbens shell of rats administered repeated cocaine.</a> J Pharmacol Exp Ther. 275 (2), 1019-1029 (1995).</li><li>Pfaff, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Drive: Molecular and physiological analyses of a simple reproductive behavior. , (1999).</li><li>Carter, C. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Postcopulatory+sexual+receptivity+in+the+female+hamster:+The+role+of+the+ovary+and+the+adrenal.">Postcopulatory sexual receptivity in the female hamster: The role of the ovary and the adrenal.</a> Horm Behav. 3 (3), 261-265 (1972).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Guide for the care and use of laboratory animals, 8th ed. , (2011).</li><li>Meisel, R. L., Camp, D. M., Robinson, T. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+microdialysis+study+of+ventral+striatal+dopamine+during+sexual+behavior+in+female+Syrian+hamsters.">A microdialysis study of ventral striatal dopamine during sexual behavior in female Syrian hamsters.</a> Beh Brain Res. 55 (2), 151-157 (1993).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> 4 Channel EEG/EMG/Biosensor Manual V005. , (2012).</li><li>Pellis, S. M., Pellis, V. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Play-fighting+differs+from+serious+play+fighting+in+both+target+of+attack+and+tactics+of+fighting+in+the+laboratory+rats+Rattus+norvegicus.">Play-fighting differs from serious play fighting in both target of attack and tactics of fighting in the laboratory rats Rattus norvegicus.</a> Aggress Behav. 13 (3), 227-242 (1987).</li><li>Pellis, S. M., Pellis, V. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+rates+of+attack,+defense+and+counterattack+during+the+developmental+decrease+in+play+fighting+by+male+and+female+rats.">Differential rates of attack, defense and counterattack during the developmental decrease in play fighting by male and female rats.</a> Dev Psychobiol. 23 (3), 215-231 (1990).</li><li>Pellis, S. M., Hastings, E., Shimizu, T., Kamitakahara, H., Komorowska, J., Forgie, M. L., Kolb, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+orbital+frontal+cortex+damage+on+the+modulation+of+defensive+responses+by+rats+in+playful+and+non-playful+social+contexts.">The effects of orbital frontal cortex damage on the modulation of defensive responses by rats in playful and non-playful social contexts.</a> Behav Neurosci. 120 (1), 72-84 (2006).</li><li>Wakabayashi, K. T., Kiyatkin, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+changes+in+extracellular+glutamate+induced+by+natural+arousing+stimuli+and+intravenous+cocaine+in+the+nucleus+accumbens+shell+and+core.">Rapid changes in extracellular glutamate induced by natural arousing stimuli and intravenous cocaine in the nucleus accumbens shell and core.</a> J Neurophysiol. 108 (1), 285-299 (2012).</li><li>Kapelsohn, K. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+methods+for+cutting,+mounting,+and+staining+tissue+for+neural+histology.">Improved methods for cutting, mounting, and staining tissue for neural histology.</a> Protoc Exch. , (2015).</li><li>Siegel, H. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chapter+7:+Male+sexual+behavior.">Chapter 7: Male sexual behavior.</a> The Hamster: Reproduction and Behavior. , (1985).</li><li>Day, J. J., Carelli, 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=The+nucleus+accumbens+and+pavlovian+reward+learning.">The nucleus accumbens and pavlovian reward learning.</a> Neuroscientist. 13 (2), 148-159 (2007).</li><li>Meisel, R. L., Mullins, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sexual+experience+in+female+rodents:+Cellular+mechanisms+and+functional+consequences.">Sexual experience in female rodents: Cellular mechanisms and functional consequences.</a> Brain Res. 1126 (1), 56-65 (2006).</li><li>Meredith, G. 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Les auteurs n’ont rien à divulguer.

Bien que relativement simple, certains problèmes peuvent survenir lorsque vous utilisez cette technique. Tout d’abord, le placement stéréotaxique des sondes doit être précis : contrairement à la microdialyse qui échantillonne un rayon plus large du milieu extracellulaire qui entoure la sonde, cette technique ne permet la mesure d’un neurotransmetteur qui entre en contact direct avec la sonde. Deuxièmement, dans le cas de l’enregistrement de la fibre de carbone, en raison de la faible largeur de fibre, rupt...

La capacité de mesurer la libération des neurotransmetteurs chez les animaux de se comporter éveillé permet aux chercheurs de comportements spécifiques avec des modèles spatiaux et temporels de la neurotransmission, un outil puissant pour étudier les mécanismes et circuits qui sous-tend tous les deux un lien naturel et les comportements opérant en temps réel. Historiquement, microdialyse a été utilisée pour mesurer les substances électriquement réactifs et non réactifs dans le milieu extracellulaire du cerveau1. Cette technique utilise un flux continu d’une solution aqueuse de composition ionique semblable au liquide extracellulaire, au moyen d’une sonde de microdialyse composée d’un petit arbre avec une pointe de membrane semi-perméable fibre creuse2. Après l’insertion de la sonde, les neurotransmetteurs ou autres analytes d’intérêt peuvent traverser la membrane semi-perméable par diffusion passive avant sont recueillis à des intervalles pour une analyse ultérieure par chromatographie liquide à haute performance (HPLC), un chimie analytique technique communément utilisée pour séparer, identifier et quantifier les composants d’un mélange hétérogène de3.
Bien que la microdialyse est une technique sensible qui peut être utilisée pour mesurer pratiquement n’importe quelle analyte d’intérêt, la résolution temporelle est faible, avec des fréquences d’échantillonnage maximale de l’ordre de minutes à quelques dizaines de minutes1,2. L’invention de la voltampérométrie cyclique de balayage rapide (FSCV), une technique qui s’appuie sur le potentiel d’oxydo-réduction des espèces électroactives, peut élucider près de concentrations instantanées de l’analyte d’intérêt dans le liquide extracellulaire. En bref (voir Robinson et al. 4 pour un examen approfondi), une électrode est appliquée pour soulever et abaisser la tension d’une manière vague triangulaire sur une échelle de temps rapide4. Lorsque la tension est dans la plage correcte, le composé d’intérêt est à plusieurs reprises oxydé et réduit. Cette oxydation et réduction se traduit par un mouvement d’électrons qui crée un petit courant alternatif. Analyse des taux aura lieu sur l’échelle de seconde avec l’oxydation et de réduction des composés qui se produisent en microsecondes. En soustrayant l’arrière-plan actuel créé par la sonde de courant qui en résulte, on peut générer une tension vs actuelle parcelle unique pour chaque composé. Étant donné que l’échelle de temps des oscillations tension est connue, ces données peuvent servir à calculer une parcelle du courant en fonction du temps. Ainsi, les concentrations relatives de ce composé peuvent être déterminées tant que le nombre d’électrons transférés dans chaque oxydation et la réaction de réduction est connue4.
Cette spécificité chimique et une haute résolution temporelle faire FSCV une technique puissante pour la détection de modification chimique concentration in vivo. Cependant, malgré ces multiples avantages, cette technique requiert une grande expertise technique et des équipements coûteux et le programme d’installation. En outre, nonelectroactive neurotransmetteurs (p. ex., glutamate) ne peuvent être mesurées à l’aide de cette technique. Heureusement, les progrès technologiques dans le domaine de l’électrochimie5, ainsi que la commercialisation de ces inventions, a introduit une approche relativement simple de mesurer non-polymères électroactifs neurotransmetteurs chez les animaux éveillés de comportement anormal sans compromettre la technique temporelle de précision-a connu comme la technologie des biocapteurs enzymatiques. Cette technique utilise la conversion enzymatique du neurotransmetteur nonelectroactive d’intérêt dans les deux substrats, dont une est électroactifs de peroxyde d’hydrogène qui est détecté comme un courant d’oxydation ampérométrique généré par un potentiel appliqué5 . Sondes de biocapteur disponible dans le commerce (voir Figure 1) mesurent sélectivement analytes d’intérêt en competitivement réduisant la contribution des interférences endogènes. Dans le cas de glutamate, la contribution de la commune interferent l’acide ascorbique (AA) est compétitif réduite au courant mesuré en localisant co oxydase AA sur la surface active enzymatique du capteur, conversion AA non-polymères électroactifs déhydroascorbate et l’eau. En outre, une couche de polymère chargée négativement Nafion présente sous la couche de l’enzyme exclut les composés anioniques endogènes.
Ce même montage expérimental de biocapteur peut mesurer électroactifs neurotransmetteurs comme FSCV, mais au lieu de cela, il emploie un enregistrement potentiel fixe6. Contrairement à la tension oscillante appliquée dans FSCV, dans un enregistrement potentiel fixe la tension est maintenue à l’oxydo-réduction potentielle pour l’analyte d’intérêt. Bien qu’il soit moins chimiquement sélectif que FSCV car plusieurs neurotransmetteurs peuvent avoir le même potentiel, de redox dans les zones cérébrales qui majoritairement incliner vers un neurotransmetteur, la nature de la clé de cette approche l’emporte sur l’absence de produit chimique spécificité.
La possibilité de mesurer des polymères électroactifs et nonelectroactive libération des neurotransmetteurs en temps quasi réel et liez-le à certains événements comportements fournit l’occasion d’examiner la libération des neurotransmetteurs convergentes. Ce manuscrit détaille l’utilisation de ce système d’interroger la neurotransmission de la dopamine et du glutamate en réponse à la récompense naturelle chez les hamsters se comporter éveillés. Le but du présent document est de détailler le processus de mesure de cette libération des neurotransmetteurs durant le comportement sexuel chez les hamsters femelles, dans le but de démontrer la faisabilité à l’examen des autres comportements et paradigmes expérimentaux.
Les hamsters sont un modèle idéal pour une utilisation dans les enregistrements électrochimiques Historiquement, modèles de rat et de souris ont été utilisés dans l’étude du comportement sexuel. Ces espèces de rongeurs se livrer à une séquence de copulation dynamique, impliquant de nombreux comportements féminin invitation qui incluent hopping, s’élançant et oreille remuant pour attirer le mâle pour chasser et finalement monter la femelle7. Le montage par le mâle (avec ou sans pénétration vaginale) dure seulement quelques secondes, pendant laquelle la femelle s’engage dans sa posture de comportement sexuel (appelée lordose) également seulement pendant quelques secondes avant de reprendre les comportements de sollicitation active. Ce modèle de comportement, composé de niveaux élevés d’activité entrecoupées de courtes périodes d’immobilité, est problématique pour la mesure de la neurotransmission dans le comportement des animaux. Tout d’abord, on peut artefacts de mouvement dans les enregistrements ampérométrique non liés à l’activité neurale. Deuxièmement, la locomotion est associée à la libération de neurotransmetteurs particuliers dans certaines régions du cerveau. Par exemple, la libération de dopamine a été couplée à l’activité locomotrice dans le striatum dorsal et ventral8,9, une constatation qui ont formé la base pour les mesures de la microdialyse de dopamine après psychostimulant administration,10. Parce que les comportements de sollicitation femelle typique MOSt rongeurs impliquent des niveaux élevés de l’activité locomotrice et sont représentés par la majeure partie d’un test de comportement sexuel de 10 minutes, ce qui rend difficile d’attribuer les changements dans la neurotransmission aux composantes du comportement sexuel explicites qui collectivement durent seulement minutes.
Pour analyser le profil neurochimique du comportement sexuel féminin, ce laboratoire chercha une espèce dans laquelle il y a une activité locomotrice minimale accompagnant le comportement sexuel. La séquence de copulation chez le hamster syrien (Mesocricetus auratus) est idéale pour les enregistrements neurochimiques en raison de l’absence de comportements de sollicitation généralement vu chez les rats et les souris11. En conséquence, hamsters femelles vont entrer et pour gérer la posture de la lordose pour plus de 9 minutes sur 10 minutes essais session12. Avec l’absence de mouvements locomoteurs étrangères par la femelle, en vivo électrochimiques enregistrements qui peuvent être associés aux éléments d’interactions sexuelles avec le mâle peuvent être obtenus.
Combats de copulation chez les hamsters Après l’introduction d’un animal mâle stimulus dans la chambre d’essai, le mâle engagera au départ dans l’enquête d’ano-génitales (IA) de la femelle avant de monter le son (Figure 2A). Afin que le mâle à la monter, la femelle doit assumer une posture sexuelle réceptive appelée lordose, dans laquelle elle arches son dos et dévie vers sa queue, afin que le mâle de montage peut accéder du pénis dans son vagin. Le mâle va monter la femelle, étreignant son arrière-train avec deux pattes (Figure 2B) et commencer à chevauchement pour tenter de gagner l’intromission du pénis (Figure 2C). Le mâle va monter la femelle (sans insertion) ainsi qu’intromit un certain nombre de fois avant d’atteindre finalement l’éjaculation. Cette séquence de montures et intromissions conduisant à l’éjaculation est appelée un « bout de copulation ». Les hommes auront plusieurs épisodes copulateurs dans une seule session.

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	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:329px;">Nembutal</td>
			<td style="width:183px;">Oak Pharmaceuticals Inc.</td>
			<td style="width:323px;">76478-501-50</td>
			<td style="width:504px;">Pentobarbital sodium injection, USP. This lab uses 8.5mg/100g body weight, injected intraperotineally.&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:329px;">Loxicom analgesic&#160;</td>
			<td style="width:183px;">Norbrook Laboratories&#160;</td>
			<td style="width:323px;">6451603670</td>
			<td style="width:504px;">NSAID antinflammatory and analgesic used for post-operative pain control. Generic: meloxicam.&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:329px;">Enroflox antibiotic&#160;</td>
			<td style="width:183px;">Norbrook Laboratories&#160;</td>
			<td style="width:323px;">5552915411</td>
			<td style="width:504px;">Fluoroquinolone antibiotic for post-operative infection prevention. Generic: Enrofloxacin.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:329px;">Beuthanasia-D&#160;</td>
			<td style="width:183px;">Merck Animal Health</td>
			<td style="width:323px;">00061047305</td>
			<td style="width:504px;">Pentobarbital Sodium, Phenytoin Sodium euthanasia agent.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bone screws</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>8111-16</td>
			<td style="width:504px;">1/8&#34; bone screw (Pkg. of 16) used to affix skull cap to skull.&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Dental acrylic (Bosworth Duz-All)</td>
			<td>Bosworth&#160;</td>
			<td>166261C&#160;</td>
			<td style="width:504px;">Self curing dental acrylic is used in construction of a skull cap to affix cannula and head mount to skull.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;">Hardware biosensor setup&#160;</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>8400-K2</td>
			<td style="width:504px;">Pinnacle offers complete hardware kits for new users of our tethered biosensor system for rats. Kits include a commutator, preamplifier, and data conditioning and acquisition system</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;">Base video computer package</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>9000-K1</td>
			<td style="width:504px;">The base computer package includes a preconfigured computer with ample hard disk storage, a high-definition monitor, a keyboard and mouse, an uninterruptible power supply, and all necessary cables.&#160;</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;">Video EQ700 EverFocus camera&#160; package</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>&#160;9000-K10&#160;</td>
			<td style="width:504px;">EQ700 night vision capable box camera with independent IR source was obtained as part of Pinnacle video computer package. Dome camera (9000-K9) and HD camera (9000-K11) options are also available.&#160;</td>
		</tr>
		<tr height="126">
			<td height="126" style="height:126px;">Sirenia Acquisition software</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>Free--available to download from pinnaclet.com</td>
			<td style="width:504px;">Sirenia&#160;Acquisition provides a single platform for recording data from any Pinnacle hardware system. The software features synchronization of all data streams, user-configurable settings, data consolidation, and multiple export options. In addition, the software includes basic review and analysis modules for biosensor recordings. Sirenia&#160;delivers free ll-in-one software that is ideal for data acquisition and review.</td>
		</tr>
		<tr height="147">
			<td height="147" style="height:147px;">Tethered rat&#160;in vitro&#160;calibration kit</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>7000-K2-T-BAS&#160;</td>
			<td style="width:504px;">In order to relate the current changes measured by a biosensor to actual changes in analyte concentration, it is necessary to calibrate the biosensor prior to implantation into the animal. The process also confirms the integrity and selectivity of the sensors.&#160;Calibration kit includes 20 mL jacketed beaker (#7058), 1/2&#34; by 1/8&#34; magnetic stir bar (#7059), right angle clamp (#7056), 2 prong single-adjustment clamp (#7055), 4-channel calibration preamplifer (#7053), and calibration holder (#7051).&#160;</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;">Stir plate&#160;</td>
			<td>Corning</td>
			<td>6795-410D</td>
			<td style="width:504px;">Corning digital Stirrer, 5&#34; x 7&#34;, 120 VAC used to spin magnetic stirrer in jacketed beaker during in vitro calibration of glutamate biosensors.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;">Water bath capable of closed loop circulation</td>
			<td>PolyScience</td>
			<td>8006A11B</td>
			<td style="width:504px;">PolyScience 8006A11B 6L Standard Digital Heated Circulating Bath, 120VAC water bath was used with plastic tubing to heat jacketed beaker to physiological temperature.&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Carbon fiber sensor with BASi rat cannulae</td>
			<td>Pinnacle Technology, Inc.</td>
			<td>7002-CFS</td>
			<td style="width:504px;">Carbon fiber electrode used for recording dopamine neurotransmission.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ag/AgCl reference electrode</td>
			<td>Pinnacle Technology, Inc.</td>
			<td>7065</td>
			<td style="width:504px;">Necessary for carbon fiber recordings.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Glutamate biosensors&#160;</td>
			<td>Pinnacle Technology, Inc.</td>
			<td>7001&#160;</td>
			<td style="width:504px;">Enzymatic biosensor probe used for recording glutamatergic neurotransmission.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">BASi guide cannulae</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>7030&#160;</td>
			<td style="width:504px;">Guide cannulae implanted into brain region of interest to guide probe.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">BASi cannula plastic headpiece for rats&#160;</td>
			<td>Pinnacle Technologies, Inc.</td>
			<td>7011&#160;</td>
			<td style="width:504px;">Headmount stabilizes probe and attaches to potentiostat.</td>
		</tr>
	</tbody>
</table>

measuring in vivo changes in extracellular neurotransmitters during naturally rewarding behaviors in female syrian hamsters

La capacité de mesurer la libération des neurotransmetteurs sur une échelle de temps rapide permet aux patrons de la neurotransmission liés à des comportements spécifiques ou des manipulations ; un outil puissant dans l’élucidation des mécanismes sous-jacents et le circuit. Alors que la technique de la microdialyse a été utilisée pendant des décennies pour mesurer presque n’importe quelle analyte d’intérêt dans le cerveau, cette technique est limitée en résolution temporelle. Alternativement, une numérisation rapide voltampérométrie cyclique est aussi bien dans le temps précis et extrêmement sensible ; Toutefois, comme cette méthode techniquement difficile repose sur l’électroactivité de l’analyte d’intérêt, la possibilité de détecter les substances nonelectroactive (p. ex., le neurotransmetteur glutamate) est éliminée. Ce livre présente en détail l’utilisation d’un système clé en main qui combine l’ampérométrie potentiel fixe et biocapteurs enzymatiques pour mesurer les neurotransmetteurs des polymères électroactifs et nonelectroactive avec la précision temporelle. Le jumelage de ces deux puissantes techniques permettant la mesure de neurotransmission phasique et tonique avec une relative facilité et permet l’enregistrement de plusieurs neurotransmetteurs simultanément. Le but de ce manuscrit est de démontrer le processus de mesure de la dopamine et du glutamate neurotransmission in vivo à l’aide d’un comportement naturellement enrichissant (c.-à-d., comportement sexuel) chez les hamsters femelles, dans le but d’afficher la faisabilité technique de ce test pour l’examen des autres comportements et paradigmes expérimentaux.

En utilisant l’électrochimique et comportementale codage méthode décrite ci-dessus, ce laboratoire a commencé à caractériser tant toniques et phasiques fluctuations de dopamine et de glutamate pendant in vivo des enregistrements du comportement sexuel. En raison de la manière dans le temps précis de cette méthodologie, nous pouvons mieux caractériser la neurotransmission lors de comportement sexuel ; en plus d’attribuer des changements dans les modes de libération...

Watch this Scientific Journal Video about Measuring In Vivo Changes in Extracellular Neurotransmitters During Naturally Rewarding Behaviors in Female Syrian Hamsters at JoVE.com

Measuring In Vivo Changes in Extracellular Neurotransmitters During Naturally Rewarding Behaviors in Female Syrian Hamsters

Ce livre présente en détail l’utilisation d’enregistrements ampérométrie potentiel fixe à l’aide d’électrodes de fibre de carbone et de la technologie de biocapteurs enzymatiques pour mesurer la libération de dopamine et du glutamate avec haute résolution temporelle lors de comportement gratifiant naturel dans le hamster femelle.

Mesurer les variations In Vivo des neurotransmetteurs extracellulaires pendant naturellement récompenser les comportements chez les femelles Hamsters syriens

The ability to measure neurotransmitter release on a rapid time scale allows patterns of neurotransmission to be linked to specific behaviors or ...

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Introduction to Psychology

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Measuring In Vivo Changes in Extracellular Neurotransmitters During Naturally Rewarding Behaviors in Female Syrian Hamsters

Biopsychology

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10.1K vues.  University of Minnesota. Ce livre présente en détail l’utilisation d’enregistrements ampérométrie potentiel fixe à l’aide d’électrodes de fibre de carbone et de la technologie de biocapteurs enzymatiques pour mesurer la libération de dopamine et du glutamate avec haute résolution temporelle lors de comportement gratifiant naturel dans le hamster femelle.

Vidéo: Measuring In Vivo Changes in Extracellular Neurotransmitters During Naturally Rewarding Behaviors in Female Syrian Hamsters

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural connectivity form during development. In mice, retinofugal projections are arranged in a topographic manner and form eye-specific layers in the Lateral Geniculate Nucleus (dLGN) of the thalamus and the Superior Colliculus (SC). The development of these precise patterns of retinofugal projections has typically been studied by labeling populations of RGCs with fluorescent dyes and tracers, such as horseradish peroxidase1-4. However, these methods are too coarse to provide insight into developmental changes in individual RGC axonal arbor morphology that are the basis of retinotopic map formation. They also do not allow for the genetic manipulation of RGCs.
Recently, electroporation has become an effective method for providing precise spatial and temporal control for delivery of charged molecules into the retina5-11. Current retinal electroporation protocols do not allow for genetic manipulation and tracing of retinofugal projections of a single or small cluster of RGCs in postnatal mice. It has been argued that postnatal in vivo electroporation is not a viable method for transfecting RGCs since the labeling efficiency is extremely low and hence requires targeting at embryonic ages when RGC progenitors are undergoing differentiation and proliferation6. 
In this video we describe an in vivo electroporation protocol for targeted delivery of genes, shRNA, and fluorescent dextrans to murine RGCs postnatally. This technique provides a cost effective, fast and relatively easy platform for efficient screening of candidate genes involved in several aspects of neural development including axon retraction, branching, lamination, regeneration and synapse formation at various stages of circuit development. In summary we describe here a valuable tool which will provide further insights into the molecular mechanisms underlying sensory map development.

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

We demonstrate an in vivo electroporation protocol for transfecting single or small clusters of retinal ganglion cells (RGCs) and other retinal cell types in postnatal mice over a wide range of ages. The ability to label and genetically manipulate postnatal RGCs in vivo is a powerful tool for developmental studies.

La transfection des cellules ganglionnaires de la rétine de la souris par In vivo L&#39;électroporation

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural ...

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Neurosciences

In vivo Laser Axotomy in C. elegans

Neurons communicate with other cells via axons and dendrites, slender membrane extensions that contain pre- or post-synaptic specializations. If a neuron is damaged by injury or disease, it may regenerate. Cell-intrinsic and extrinsic factors influence the ability of a neuron to regenerate and restore function. Recently, the nematode C. elegans has emerged as an excellent model organism to identify genes and signaling pathways that influence the regeneration of neurons1-6. The main way to initiate neuronal regeneration in C. elegans is laser-mediated cutting, or axotomy. During axotomy, a fluorescently-labeled neuronal process is severed using high-energy pulses. Initially, neuronal regeneration in C. elegans was examined using an amplified femtosecond laser5. However, subsequent regeneration studies have shown that a conventional pulsed laser can be used to accurately sever neurons in vivo and elicit a similar regenerative response1,3,7.
We present a protocol for performing in vivo laser axotomy in the worm using a MicroPoint pulsed laser, a turnkey system that is readily available and that has been widely used for targeted cell ablation. We describe aligning the laser, mounting the worms, cutting specific neurons, and assessing subsequent regeneration. The system provides the ability to cut large numbers of neurons in multiple worms during one experiment. Thus, laser axotomy as described herein is an efficient system for initiating and analyzing the process of regeneration.

In vivo Laser Axotomy in C. elegans

A protocol to cut neurons in C. elegans with a MicroPoint pulsed laser is presented. We describe setting up the system, immobilizing worms, and severing labeled neurons. Advantages include a relatively low-cost system and the ability to sever neuronal processes or ablate cells in vivo.

In vivo laser axotomie en C. elegans

Neurons communicate with other cells via axons and dendrites, slender membrane extensions that contain pre- or post-synaptic specializations. If a neuron ...

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from individual neurons are critical for understanding how neural circuits function under natural conditions. Traditionally, these recordings have been performed 'blind', meaning the identity of the recorded cell is unknown at the start of the recording. Cellular identity can be subsequently determined via intracellular1, juxtacellular2 or loose-patch3 iontophoresis of dye, but these recordings cannot be pre-targeted to specific neurons in regions with functionally heterogeneous cell types. Fluorescent proteins can be expressed in a cell-type specific manner permitting visually-guided single-cell electrophysiology4-6. However, there are many model systems for which these genetic tools are not available. Even in genetically accessible model systems, the desired promoter may be unknown or genetically homogenous neurons may have varying projection patterns. Similarly, viral vectors have been used to label specific subgroups of projection neurons7, but use of this method is limited by toxicity and lack of trans-synaptic specificity. Thus, additional techniques that offer specific pre-visualization to record from identified single neurons in vivo are needed. Pre-visualization of the target neuron is particularly useful for challenging recording conditions, for which classical single-cell recordings are often prohibitively difficult8-11. The novel technique described in this paper uses retrograde transport of a fluorescent dye applied using tungsten needles to rapidly and selectively label a specific subset of cells within a particular brain region based on their unique axonal projections, thereby providing a visual cue to obtain targeted electrophysiological recordings from identified neurons in an intact circuit within a vertebrate CNS.
The most significant novel advancement of our method is the use of fluorescent labeling to target specific cell types in a non-genetically accessible model system. Weakly electric fish are an excellent model system for studying neural circuits in awake, behaving animals12. We utilized this technique to study sensory processing by "small cells" in the anterior exterolateral nucleus (ELa) of weakly electric mormyrid fish. "Small cells" are hypothesized to be time comparator neurons important for detecting submillisecond differences in the arrival times of presynaptic spikes13. However, anatomical features such as dense myelin, engulfing synapses, and small cell bodies have made it extremely difficult to record from these cells using traditional methods11, 14. Here we demonstrate that our novel method selectively labels these cells in 28% of preparations, allowing for reliable, robust recordings and characterization of responses to electrosensory stimulation.

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

Retrograde transport of fluorescent dye labels a sub-population of neurons based on anatomical projection. Labeled axons can be visually targeted in vivo, permitting extracellular recording from identified axons. This technique facilitates recording when neurons cannot be labeled through genetic manipulation or are difficult to isolate using 'blind' in vivo approaches.

Marquage fluorescent rétrograde Permet ciblée extracellulaire seule unité d&#39;enregistrement de neurones identifiés<em&gt; In vivo</em

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from ...

Functional Neuroimaging Using Ultrasonic Blood-brain Barrier Disruption and Manganese-enhanced MRI

Although mice are the dominant model system for studying the genetic and molecular underpinnings of neuroscience, functional neuroimaging in mice remains technically challenging. One approach, Activation-Induced Manganese-enhanced MRI (AIM MRI), has been used successfully to map neuronal activity in rodents 1-5. In AIM MRI, Mn2+ acts a calcium analog and accumulates in depolarized neurons 6,7. Because Mn2+ shortens the T1 tissue property, regions of elevated neuronal activity will enhance in MRI. Furthermore, Mn2+ clears slowly from the activated regions; therefore, stimulation can be performed outside the magnet prior to imaging, enabling greater experimental flexibility. However, because Mn2+ does not readily cross the blood-brain barrier (BBB), the need to open the BBB has limited the use of AIM MRI, especially in mice.
One tool for opening the BBB is ultrasound. Though potentially damaging, if ultrasound is administered in combination with gas-filled microbubbles (i.e., ultrasound contrast agents), the acoustic pressure required for BBB opening is considerably lower. This combination of ultrasound and microbubbles can be used to reliably open the BBB without causing tissue damage 8-11.
Here, a method is presented for performing AIM MRI by using microbubbles and ultrasound to open the BBB. After an intravenous injection of perflutren microbubbles, an unfocused pulsed ultrasound beam is applied to the shaved mouse head for 3 minutes. For simplicity, we refer to this technique of BBB Opening with Microbubbles and UltraSound as BOMUS 12. Using BOMUS to open the BBB throughout both cerebral hemispheres, manganese is administered to the whole mouse brain. After experimental stimulation of the lightly sedated mice, AIM MRI is used to map the neuronal response.
To demonstrate this approach, herein BOMUS and AIM MRI are used to map unilateral mechanical stimulation of the vibrissae in lightly sedated mice 13. Because BOMUS can open the BBB throughout both hemispheres, the unstimulated side of the brain is used to control for nonspecific background stimulation. The resultant 3D activation map agrees well with published representations of the vibrissae regions of the barrel field cortex 14. The ultrasonic opening of the BBB is fast, noninvasive, and reversible; and thus this approach is suitable for high-throughput and/or longitudinal studies in awake mice.

A technique is described for broadly opening the blood-brain barrier in the mouse using microbubbles and ultrasound. Using this technique, manganese can be administered to the mouse brain. Because manganese is an MRI contrast agent that accumulates in depolarized neurons, this approach enables imaging of neuronal activity.

Utilisation de neuro-imagerie fonctionnelle par ultrasons rupture de la barrière hémato-encéphalique et le manganèse-IRM

Although mice are the dominant model system for studying the genetic and molecular underpinnings of neuroscience, functional neuroimaging in mice remains ...

Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs through activation of their ion channels and neurotransmitter receptors, and process information in part through activity-dependent release of gliotransmitters. Furthermore, astrocytes constitute the main uptake system for glutamate, contribute to potassium spatial buffering, as well as to GABA clearance. These cells therefore constantly monitor synaptic activity, and are thereby sensitive indicators for alterations in synaptically-released glutamate, GABA and extracellular potassium levels. Additionally, alterations in astroglial uptake activity or buffering capacity can have severe effects on neuronal functions, and might be overlooked when characterizing physiopathological situations or knockout mice. Dual recording of neuronal and astroglial activities is therefore an important method to study alterations in synaptic strength associated to concomitant changes in astroglial uptake and buffering capacities. Here we describe how to prepare hippocampal slices, how to identify stratum radiatum astrocytes, and how to record simultaneously neuronal and astroglial electrophysiological responses. Furthermore, we describe how to isolate pharmacologically the synaptically-evoked astroglial currents.

The preparation of acute brain slices from isolated hippocampi, as well as the simultaneous electrophysiological recordings of astrocytes and neurons in stratum radiatum during stimulation of schaffer collaterals is described. The pharmacological isolation of astroglial potassium and glutamate transporter currents is demonstrated.

Deux enregistrements électrophysiologiques des synapses-réponses évoquées astrogliales et neuronales aiguës dans des coupes d&#39;hippocampe

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs ...

In Vivo Two-photon Imaging Of Experience-dependent Molecular Changes In Cortical Neurons

The brain's ability to change in response to experience is essential for healthy brain function, and abnormalities in this process contribute to a variety of brain disorders1,2. To better understand the mechanisms by which brain circuits react to an animal's experience requires the ability to monitor the experience-dependent molecular changes in a given set of neurons, over a prolonged period of time, in the live animal. While experience and associated neural activity is known to trigger gene expression changes in neurons1,2, most of the methods to detect such changes do not allow repeated observation of the same neurons over multiple days or do not have sufficient resolution to observe individual neurons3,4. Here, we describe a method that combines in vivo two-photon microscopy with a genetically encoded fluorescent reporter to track experience-dependent gene expression changes in individual cortical neurons over the course of day-to-day experience. 
One of the well-established experience-dependent genes is Activity-regulated cytoskeletal associated protein (Arc)5,6. The transcription of Arc is rapidly and highly induced by intensified neuronal activity3, and its protein product regulates the endocytosis of glutamate receptors and long-term synaptic plasticity7. The expression of Arc has been widely used as a molecular marker to map neuronal circuits involved in specific behaviors3. In most of those studies, Arc expression was detected by in situ hybridization or immunohistochemistry in fixed brain sections. Although those methods revealed that the expression of Arc was localized to a subset of excitatory neurons after behavioral experience, how the cellular patterns of Arc expression might change with multiple episodes of repeated or distinctive experiences over days was not investigated. 
In vivo two-photon microscopy offers a powerful way to examine experience-dependent cellular changes in the living brain8,9. To enable the examination of Arc expression in live neurons by two-photon microscopy, we previously generated a knock-in mouse line in which a GFP reporter is placed under the control of the endogenous Arc promoter10. This protocol describes the surgical preparations and imaging procedures for tracking experience-dependent Arc-GFP expression patterns in neuronal ensembles in the live animal. In this method, chronic cranial windows were first implanted in Arc-GFP mice over the cortical regions of interest. Those animals were then repeatedly imaged by two-photon microscopy after desired behavioral paradigms over the course of several days. This method may be generally applicable to animals carrying other fluorescent reporters of experience-dependent molecular changes4.

In Vivo Two-photon Imaging Of Experience-dependent Molecular Changes In Cortical Neurons

Experience-dependent molecular changes in neurons are essential for the brain's ability to adapt in response to behavioral challenges. An in vivo two-photon imaging method is described here that allows the tracking of such molecular changes in individual cortical neurons through genetically encoded reporters.

In Vivo Imagerie biphotonique d&#39;expérience qui dépendent des changements moléculaires dans les neurones corticaux

The brain's ability to change in response to experience is essential for healthy brain function, and abnormalities in this process contribute to a variety ...

Ex Vivo Preparations of the Intact Vomeronasal Organ and Accessory Olfactory Bulb

The mouse accessory olfactory system (AOS) is a specialized sensory pathway for detecting nonvolatile social odors, pheromones, and kairomones. The first neural circuit in the AOS pathway, called the accessory olfactory bulb (AOB), plays an important role in establishing sex-typical behaviors such as territorial aggression and mating. This small (&#60;1 mm3) circuit possesses the capacity to distinguish unique behavioral states, such as sex, strain, and stress from chemosensory cues in the secretions and excretions of conspecifics. While the compact organization of this system presents unique opportunities for recording from large portions of the circuit simultaneously, investigation of sensory processing in the AOB remains challenging, largely due to its experimentally disadvantageous location in the brain. Here, we demonstrate a multi-stage dissection that removes the intact AOB inside a single hemisphere of the anterior mouse skull, leaving connections to both the peripheral vomeronasal sensory neurons (VSNs) and local neuronal circuitry intact. The procedure exposes the AOB surface to direct visual inspection, facilitating electrophysiological and optical recordings from AOB circuit elements in the absence of anesthetics. Upon inserting a thin cannula into the vomeronasal organ (VNO), which houses the VSNs, one can directly expose the periphery to social odors and pheromones while recording downstream activity in the AOB. This procedure enables controlled inquiries into AOS information processing, which can shed light on mechanisms linking pheromone exposure to changes in behavior.

Ex Vivo Preparations of the Intact Vomeronasal Organ and Accessory Olfactory Bulb

The mouse accessory olfactory bulb (AOB) has been difficult to study in the context of sensory coding. Here, we demonstrate a dissection that produces an ex vivo preparation in which AOB neurons remain functionally connected to their peripheral inputs, facilitating research into information processing of mouse pheromones and kairomones.

Ex Vivo préparatifs de l&#39;ampoule Vomeronasal organes et accessoire olfactive Intact

The mouse accessory olfactory system (AOS) is a specialized sensory pathway for detecting nonvolatile social odors, pheromones, and kairomones. The first ...

A Simple and Inexpensive Method for Determining Cold Sensitivity and Adaptation in Mice

Cold hypersensitivity is a serious clinical problem, affecting a broad subset of patients and causing significant decreases in quality of life. The cold plantar assay allows the objective and inexpensive assessment of cold sensitivity in mice, and can quantify both analgesia and hypersensitivity. Mice are acclimated on a glass plate, and a compressed dry ice pellet is held against the glass surface underneath the hindpaw. The latency to withdrawal from the cooling glass is used as a measure of cold sensitivity.
Cold sensation is also important for survival in regions with seasonal temperature shifts, and in order to maintain sensitivity animals must be able to adjust their thermal response thresholds to match the ambient temperature. The Cold Plantar Assay (CPA) also allows the study of adaptation to changes in ambient temperature by testing the cold sensitivity of mice at temperatures ranging from 30 &#176;C to 5 &#176;C. Mice are acclimated as described above, but the glass plate is cooled to the desired starting temperature using aluminum boxes (or aluminum foil packets) filled with hot water, wet ice, or dry ice. The temperature of the plate is measured at the center using a filament T-type thermocouple probe. Once the plate has reached the desired starting temperature, the animals are tested as described above.
This assay allows testing of mice at temperatures ranging from innocuous to noxious. The CPA yields unambiguous and consistent behavioral responses in uninjured mice and can be used to quantify both hypersensitivity and analgesia. This protocol describes how to use the CPA to measure cold hypersensitivity, analgesia, and adaptation in mice.

The Cold Plantar Assay (CPA) measures cold responsiveness between 30 &#176;C and 5 &#176;C, and can also measure cold adaptation. This protocol describes how to use the CPA to measure cold hypersensitivity, analgesia, and adaptation in mice.

Une méthode simple et peu coûteuse pour déterminer Sensibilité au froid et adaptation chez la souris

Cold hypersensitivity is a serious clinical problem, affecting a broad subset of patients and causing significant decreases in quality of life.  The cold ...

Simultaneous ex vivo Functional Testing of Two Retinas by in vivo Electroretinogram System

An In vivo electroretinogram (ERG) signal is composed of several overlapping components originating from different retinal cell types, as well as noise from extra-retinal sources. Ex vivo ERG provides an efficient method to dissect the function of retinal cells directly from an intact isolated retina of animals or donor eyes. In addition, ex vivo ERG can be used to test the efficacy and safety of potential therapeutic agents on retina tissue from animals or humans. We show here how commercially available in vivo ERG systems can be used to conduct ex vivo ERG recordings from isolated mouse retinas. We combine the light stimulation, electronic and heating units of a standard in vivo system with custom-designed specimen holder, gravity-controlled perfusion system and electromagnetic noise shielding to record low-noise ex vivo ERG signals simultaneously from two retinas with the acquisition software included in commercial in vivo systems. Further, we demonstrate how to use this method in combination with pharmacological treatments that remove specific ERG components in order to dissect the function of certain retinal cell types.

Simultaneous ex vivo Functional Testing of Two Retinas by in vivo Electroretinogram System

Ex vivo ERG can be used to record electrical activity of retinal cells directly from isolated intact retinas of animals or humans. We demonstrate here how common in vivo ERG systems can be adapted for ex vivo ERG recordings in order to dissect the electrical activity of retinal cells.

Simultané<em&gt; Ex vivo</em&gt; Tests fonctionnels de deux rétines par<em&gt; In vivo</em&gt; Système Électrorétinogramme

An In vivo electroretinogram (ERG) signal is composed of several overlapping components originating from different retinal cell types, as well as noise ...

Construction of Cell-based Neurotransmitter Fluorescent Engineered Reporters (CNiFERs) for Optical Detection of Neurotransmitters In Vivo

Cell-based neurotransmitter fluorescent engineered reporters (CNiFERs) provide a new tool for neuroscientists to optically detect the release of neurotransmitters in the brain in vivo. A specific CNiFER is created from a human embryonic kidney cell that stably expresses a specific G protein-coupled receptor, which couples to Gq/11 G proteins, and a FRET-based Ca2+-detector, TN-XXL. Activation of the receptor leads to an increase in the FRET signal. CNiFERs have nM sensitivity and a temporal response of seconds because a CNiFER clone utilizes the native receptor for a particular neurotransmitter, e.g., D2R for dopamine. CNiFERs are directly implanted into the brain, enabling them to sense neurotransmitter release with a spatial resolution of less than one hundred &#181;m, making them ideal to measure volume transmission in vivo. CNiFERs can also be used to screen other drugs for potential cross-reactivity in vivo. We recently expanded the family of CNiFERs to include GPCRs that couple to Gi/o G proteins. CNiFERs are available for detecting acetylcholine (ACh), dopamine (DA) and norepinephrine (NE). Given that any GPCR can be used to create a novel CNiFER and that there are approximately 800 GPCRs in the human genome, we describe here the general procedure to design, realize, and test any type of CNiFER.

Construction of Cell-based Neurotransmitter Fluorescent Engineered Reporters CNiFERs for Optical Detection of Neurotransmitters In Vivo

We present a protocol to create cell-based neurotransmitter fluorescent engineered reporters (CNiFERs) for the optical detection of volumetric neurotransmitter release.

La construction de base de cellules fluorescentes neurotransmetteur Engineered Reporters (CNiFERs) pour la détection optique des neurotransmetteurs<em&gt; In Vivo</em