Name: combined infusion and stimulation with fast-scan cyclic voltammetry (cis-fscv) to assess ventral tegmental area receptor regulation of phasic dopamine
Uploaded: 2020-04-23T14:00:00
Description: Watch this Scientific Journal Video about Combined Infusion and Stimulation with Fast-Scan Cyclic Voltammetry CIS-FSCV to Assess Ventral Tegmental Area Receptor Regulation of Phasic Dopamine at JoVE.c

Work was supported by Elizabethtown College (R.J.W, M.L., and L.M.), by a NSF Graduate Fellowship (R.J.W.) and by the Yale School of Medicine (N.A.).

All experiments were conducted according to the National Institutes of Health (NIH) Guide for the Care and Use of Laboratory Animals and were approved by both Elizabethtown College and Yale University Institutional Animal Care and Use Committee (IACUC). This protocol is specific to the anesthetized rat preparation of utilizing CIS-FSCV.
1. Presurgical preparations
<ol>
	<li>Electrode solution preparation
	<ol>
		<li>To make the electrode backfill solution, prepare a solution of 4 M potassium...

<ol>
	<li>Grace, A. A., Bunney, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+control+of+firing+pattern+in+nigral+dopamine+neurons:+burst+firing.">The control of firing pattern in nigral dopamine neurons: burst firing.</a> Journal of Neuroscience. 4 (11), 2877-2890 (1984).</li><li>Lester, D. B., 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=Midbrain+acetylcholine+and+glutamate+receptors+modulate+accumbal+dopamine+release.">Midbrain acetylcholine and glutamate receptors modulate accumbal dopamine release.</a> Neuroreport. 19 (9), 991-995 (2008).</li><li>Lodge, D. J., Grace, A. 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Y., 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=Expression+of+functional+cannabinoid+CB2+receptor+in+VTA+dopamine+neurons+in+rats.">Expression of functional cannabinoid CB2 receptor in VTA dopamine neurons in rats.</a> Addiction Biology. 22 (3), 752-765 (2017).</li><li>Wickham, R. J., 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=Advances+in+studying+phasic+dopamine+signaling+in+brain+reward+mechanisms.">Advances in studying phasic dopamine signaling in brain reward mechanisms.</a> Frontiers in Bioscience. 5, 982-999 (2013).</li><li>Wightman, R. M., 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=Monitoring+of+transmitter+metabolites+by+voltammetry+in+cerebrospinal+fluid+following+neural+pathway+stimulation.">Monitoring of transmitter metabolites by voltammetry in cerebrospinal fluid following neural pathway stimulation.</a> Nature. 262 (5564), 145-146 (1976).</li><li>Grace, A. A., Bunney, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+control+of+firing+pattern+in+nigral+dopamine+neurons:+single+spike+firing.">The control of firing pattern in nigral dopamine neurons: single spike firing.</a> Journal of Neuroscience. 4 (11), 2866-2876 (1984).</li><li>Mameli-Engvall, M., 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=Hierarchical+control+of+dopamine+neuron-firing+patterns+by+nicotinic+receptors.">Hierarchical control of dopamine neuron-firing patterns by nicotinic receptors.</a> Neuron. 50 (6), 911-921 (2006).</li><li>Wickham, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventral+tegmental+area+alpha6beta2+nicotinic+acetylcholine+receptors+modulate+phasic+dopamine+release+in+the+nucleus+accumbens+core.">Ventral tegmental area alpha6beta2 nicotinic acetylcholine receptors modulate phasic dopamine release in the nucleus accumbens core.</a> Psychopharmacology. 229 (1), 73-82 (2013).</li><li>Solecki, W., 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=Differential+role+of+ventral+tegmental+area+acetylcholine+and+N-methyl-D-aspartate+receptors+in+cocaine-seeking.">Differential role of ventral tegmental area acetylcholine and N-methyl-D-aspartate receptors in cocaine-seeking.</a> Neuropharmacology. 75, 9-18 (2013).</li><li>John, C. E., Jones, S. R., Michael, A. C., Borland, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fast+Scan+Cyclic+Voltammetry+of+Dopamine+and+Serotonin+in+Mouse+Brain+Slices.">Fast Scan Cyclic Voltammetry of Dopamine and Serotonin in Mouse Brain Slices.</a> Electrochemical Methods for Neuroscience. , (2007).</li><li>Rice, M. E., Cragg, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nicotine+amplifies+reward-related+dopamine+signals+in+striatum.">Nicotine amplifies reward-related dopamine signals in striatum.</a> Nature Neuroscience. 7 (6), 583-584 (2004).</li><li>Espana, R. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypocretin+1/orexin+A+in+the+ventral+tegmental+area+enhances+dopamine+responses+to+cocaine+and+promotes+cocaine+self-administration.">Hypocretin 1/orexin A in the ventral tegmental area enhances dopamine responses to cocaine and promotes cocaine self-administration.</a> Psychopharmacology. 214 (2), 415-426 (2011).</li><li>Addy, N. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+L-type+calcium+channel+blocker,+isradipine,+attenuates+cue-induced+cocaine-seeking+by+enhancing+dopaminergic+activity+in+the+ventral+tegmental+area+to+nucleus+accumbens+pathway.">The L-type calcium channel blocker, isradipine, attenuates cue-induced cocaine-seeking by enhancing dopaminergic activity in the ventral tegmental area to nucleus accumbens pathway.</a> Neuropsychopharmacology. 43 (12), 2361-2372 (2018).</li><li>Hermans, A., Wightman, 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=Conical+tungsten+tips+as+substrates+for+the+preparation+of+ultramicroelectrodes.">Conical tungsten tips as substrates for the preparation of ultramicroelectrodes.</a> Langmuir. 22 (25), 10348-10353 (2006).</li><li>Borland, L. M., Michael, A. C., Borland, L. M., Michael, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Introduction+to+Electrochemical+Methods+in+Neuroscience.">An Introduction to Electrochemical Methods in Neuroscience.</a> Electrochemical Methods for Neuroscience. , (2007).</li><li>Mundroff, M. L., Wightman, 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=Amperometry+and+cyclic+voltammetry+with+carbon+fiber+microelectrodes+at+single+cells.">Amperometry and cyclic voltammetry with carbon fiber microelectrodes at single cells.</a> Current Protocols in Neuroscience. 6 (6), 14 (2002).</li><li>Rodeberg, N. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hitchhiker's+Guide+to+Voltammetry:+Acute+and+Chronic+Electrodes+for+in+vivo+Fast-Scan+Cyclic+Voltammetry.">Hitchhiker's Guide to Voltammetry: Acute and Chronic Electrodes for in vivo Fast-Scan Cyclic Voltammetry.</a> ACS Chemical Neuroscience. 8 (2), 221-234 (2017).</li><li>Sabeti, J., Gerhardt, G. A., Zahniser, N. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chloral+hydrate+and+ethanol,+but+not+urethane,+alter+the+clearance+of+exogenous+dopamine+recorded+by+chronoamperometry+in+striatum+of+unrestrained+rats.">Chloral hydrate and ethanol, but not urethane, alter the clearance of exogenous dopamine recorded by chronoamperometry in striatum of unrestrained rats.</a> Neuroscience Letters. 343 (1), 9-12 (2003).</li><li>Masuzawa, M., 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=Pentobarbital+inhibits+ketamine-induced+dopamine+release+in+the+rat+nucleus+accumbens:+a+microdialysis+study.">Pentobarbital inhibits ketamine-induced dopamine release in the rat nucleus accumbens: a microdialysis study.</a> Anesthesia &amp; Analgesia. 96 (1), 148-152 (2003).</li><li>Montague, P. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+gain+control+of+dopamine+delivery+in+freely+moving+animals.">Dynamic gain control of dopamine delivery in freely moving animals.</a> Journal of Neuroscience. 24 (7), 1754-1759 (2004).</li><li>Keithley, R. B., 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=Higher+sensitivity+dopamine+measurements+with+faster-scan+cyclic+voltammetry.">Higher sensitivity dopamine measurements with faster-scan cyclic voltammetry.</a> Analytical Chemistry. 83 (9), 3563-3571 (2011).</li><li>Jackson, B. P., Dietz, S. M., Wightman, R. 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CIS-FSCV provides a unique opportunity to investigate VTA receptor mechanisms underlying phasic DA release. There are two critical steps in order to ensure a proper recording. First, a stable baseline recording must be achieved, with little drift in the evoked DA signal. An important way to increase the likelihood of establishing a stable recording is to ensure that the electrode has had plenty of time to cycle at both 60 Hz and 10 Hz (typically 15 min at 60 Hz, and 10 min at 10 Hz). As the carbon fiber is being cycled, ...

Phasic dopamine (DA) release from the ventral tegmental area (VTA) to the nucleus accumbens (NAc) plays a vital role in reward-related behaviors. VTA DA neurons switch from a tonic-like firing (3-8 Hz) to a burst-like firing (&#62;14 Hz)1, which produces phasic DA release in the NAc. The VTA expresses a variety of somatodendritic receptors that are well-positioned to control the switch from tonic to burst-firing2,3,4,5. Identifying which of these receptors, and their respective inputs, control phasic DA release will deepen our understanding of how the reward-related circuitry is organized. The purpose of the methodology described here, combined infusion and stimulation with fast-scan cyclic voltammetry (CIS-FSCV), is to quickly and robustly assess the functionality of VTA receptors in driving phasic DA release.
The term combined infusion and stimulation (CIS) refers to pharmacologically manipulating receptors on a group of neurons (here the VTA) and stimulating those neurons to study the receptor&#39;s function. In the anesthetized rat, we electrically stimulate the VTA to evoke a large phasic DA signal (1-2 &#181;M) in the NAc core, as measured by fast-scan cyclic voltammetry (FSCV). Infusions of pharmacological drugs (i.e., receptor agonists/antagonists) at the stimulation site can be used to measure the function of VTA receptors by observing the subsequent change in evoked phasic DA release. FSCV is an electrochemical approach that enjoys both high spatial (50-100 &#181;m) and temporal (10 Hz) resolution, and is well-suited to measure reward-related, phasic DA events6,7. This resolution is finer than other in vivo neurochemical measurements, such as microdialysis. Thus, together, CIS-FSCV is well-suited to assess VTA receptor regulation of phasic dopamine release.
One common way to investigate VTA receptor function is by using a combination of electrophysiological approaches that address how those receptors alter the firing rate of neurons1,8. These studies are highly valuable in understanding what receptors are involved in driving DA firing upon activation. However, these studies can only suggest what might happen downstream at the axon terminal (i.e., release of a neurotransmitter). CIS-FSCV builds on these electrophysiological studies by answering how the output of VTA burst-firing, phasic DA release, is regulated by receptors located on VTA dendrites and cell bodies. Thus, CIS-FSCV is well-suited to build on these electrophysiology studies. As an example, nicotinic receptor activation can induce burst-firing in the VTA9, and CIS-FSCV in the anesthetized rat was used to show that nicotinic acetylcholine receptor (nAChR) activation in the VTA also controls phasic DA release in the NAc10,11.
Mechanistic examination of phasic DA regulation is also commonly studied using slice preparations alongside with bath application of drugs. These studies often focus on the presynaptic regulation of phasic DA release from dopamine terminals, as the cell bodies are often removed from the slice12. These preparations are valuable for studying presynaptic receptor effects on dopamine terminals, whereas CIS-FSCV is better suited to study somatodendritic receptor effects on dopamine neurons, as well as presynaptic inputs to the VTA. This distinction is important, because somatodendritic receptor activation in the VTA may have a different effect than NAc presynaptic receptor activation. Indeed, blocking dopaminergic presynaptic nAChRs in the NAc can elevate phasic dopamine release during burst-firing13, whereas the opposite is true at VTA somatodendritc nAChRs10,11.
CIS-FSCV is an ideal approach for studying the ability of VTA receptors to regulate phasic DA release. Importantly, this approach can be performed in an intact rat, either anesthetized or free moving. This approach is suitable for acute studies, to study receptor function in its baseline state10,14 as well as long-term studies that can assess functional changes in a receptor after drug exposure or behavioral manipulation11,15.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Electrode Filling Solution/Supplies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Micropipette</td>
			<td>World Precision Instruments</td>
			<td>MF286-5 (28 gauge)</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium Acetate</td>
			<td>Sigma</td>
			<td>236497-100G</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium Chloride</td>
			<td>Sigma</td>
			<td>P3911-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrode Supplies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Carbon fiber</td>
			<td>Thornel</td>
			<td>T650</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrode puller</td>
			<td>Narishige International</td>
			<td>PE-22</td>
			<td>Note: horizontal pullers can be used as well</td>
		</tr>
		<tr>
			<td>Glass capillary</td>
			<td>A-M systems</td>
			<td>626000</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulated wires for electrodes</td>
			<td>Weico Wire and Cable Incorporated</td>
			<td>UL 1423</td>
			<td>Length; 10 cm; diameter,0.4mm; must get custom made; insulated material should cover 5 cm of the wire</td>
		</tr>
		<tr>
			<td>Light Microscope (for viewing and cutting electrode)</td>
			<td>Fischer Scientific</td>
			<td>M3700</td>
			<td></td>
		</tr>
		<tr>
			<td>Pin</td>
			<td>Phoenix Enterprises</td>
			<td>HWS1646</td>
			<td>To be soldered onto the insuled electrode wire and reference electrode; connects to headstage</td>
		</tr>
		<tr>
			<td>Putty</td>
			<td>Alcolin</td>
			<td><a target="_blank" href="https://www.dickblick.com/items/23922-1003/">23922-1003</a></td>
			<td>Used to place electrode on while cutting the carbon fiber</td>
		</tr>
		<tr>
			<td>Scalpal Blade</td>
			<td>World Precision Instruments</td>
			<td>500239</td>
			<td>For cutting carbon fiber to the apprpriate length</td>
		</tr>
		<tr>
			<td>Silver Wire</td>
			<td>Sigma</td>
			<td>327026-4G</td>
			<td></td>
		</tr>
		<tr>
			<td>FSCV Hardware/Software</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Faraday Cage</td>
			<td>U-Line</td>
			<td>H-3618 (36&#34; x 24&#34; x 42&#34;)</td>
			<td></td>
		</tr>
		<tr>
			<td>Potentiostat</td>
			<td>Univ. of N. Carolina, Electronics Facility</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stimulating electrode</td>
			<td>PlasticsOne</td>
			<td>MS303/2-A/SPC</td>
			<td>when ordering, request a 22 mm cut below pedestal</td>
		</tr>
		<tr>
			<td>TarHeel HDCV Software</td>
			<td>University of North Carolina-Chapel Hill</td>
			<td>-</td>
			<td><a href="https://chem.unc.edu/critcl-main/criticl-electronics/criticl-electronics-hardware/" target="_blank">https://chem.unc.edu/critcl-main/criticl-electronics/criticl-electronics-hardware/</a> for ordering information</td>
		</tr>
		<tr>
			<td>UEI breakout box</td>
			<td>Univ. of N. Carolina, Electronics Facility</td>
			<td></td>
			<td><a href="https://chem.unc.edu/critcl-main/criticl-electronics/criticl-electronics-hardware/" target="_blank">https://chem.unc.edu/critcl-main/criticl-electronics/criticl-electronics-hardware/</a> for ordering information</td>
		</tr>
		<tr>
			<td>UEI power supply</td>
			<td>Univ. of N. Carolina, Electronics Facility</td>
			<td></td>
			<td><a href="https://chem.unc.edu/critcl-main/criticl-electronics/criticl-electronics-hardware/" target="_blank">https://chem.unc.edu/critcl-main/criticl-electronics/criticl-electronics-hardware/</a> for ordering information</td>
		</tr>
		<tr>
			<td>Stimulator Hardware</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Neurolog stimulus isolator</td>
			<td>Digitimer Ltd.</td>
			<td>DS4</td>
			<td>Neurolog 800A</td>
		</tr>
		<tr>
			<td>Infusion/Stimulation Supplies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Infusion Pump</td>
			<td>New Era Syringe Pump</td>
			<td>NE-300</td>
			<td></td>
		</tr>
		<tr>
			<td>Internal Cannula</td>
			<td>PlasticsOne</td>
			<td>C315I/SPC INTERNAL 33GA</td>
			<td></td>
		</tr>
		<tr>
			<td>Microliter Syringe</td>
			<td>Hamilton</td>
			<td>80308</td>
			<td></td>
		</tr>
		<tr>
			<td>Tubing</td>
			<td>PlasticsOne</td>
			<td>C313CT/ PKG TUBING 023 X 050 PE50</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical Supplies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cannula Holder</td>
			<td>Kopf Instruments</td>
			<td>1776 P-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Cotton Tip Applicators</td>
			<td>Vitality Medical</td>
			<td>806</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrode Holder</td>
			<td>Kopf Instruments</td>
			<td>1770</td>
			<td></td>
		</tr>
		<tr>
			<td>Heating Pad</td>
			<td>Kent Scientific</td>
			<td>RT-0501</td>
			<td></td>
		</tr>
		<tr>
			<td>Povidone Iodine</td>
			<td>Vitality Medical</td>
			<td>29906-004</td>
			<td></td>
		</tr>
		<tr>
			<td>Screws</td>
			<td>Stoelting</td>
			<td>Bone Anchor Screws/Pkg.of 100</td>
			<td>1.59 mm O.D., 3.2 mm long</td>
		</tr>
		<tr>
			<td>Silver wire reference with AgCl</td>
			<td>InVivo Metric</td>
			<td>E255A</td>
			<td></td>
		</tr>
		<tr>
			<td>Square Gauze</td>
			<td>Vitality Medical</td>
			<td>441408</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereotax</td>
			<td>Kopf Instruments</td>
			<td>Model 902 (Dual Arm Bar)</td>
			<td></td>
		</tr>
		<tr>
			<td>Histological Supplies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Formulin</td>
			<td>Sigma</td>
			<td>1004960700</td>
			<td></td>
		</tr>
		<tr>
			<td>Power supply</td>
			<td>BK Precision</td>
			<td>9110</td>
			<td></td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Sigma</td>
			<td>80497</td>
			<td></td>
		</tr>
		<tr>
			<td>Tungsten microelectrode</td>
			<td>MicroProbes</td>
			<td>WE30030.5A3</td>
			<td></td>
		</tr>
		<tr>
			<td>Drugs for infusions</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>((2R)-amino-5-phosphonovaleric acid</td>
			<td>Sigma Aldrich</td>
			<td>A5282</td>
			<td></td>
		</tr>
		<tr>
			<td>N-methyl-D-aspartate</td>
			<td>Sigma Aldrich</td>
			<td>M3262</td>
			<td></td>
		</tr>
		<tr>
			<td>Mecamylamine hydrochloride (M9020-5mg)</td>
			<td>Sigma Aldrich</td>
			<td>M9020</td>
			<td></td>
		</tr>
		<tr>
			<td>Scopolamine hydrobromide (S0929-1g)</td>
			<td>Sigma Aldrich</td>
			<td>S0929</td>
			<td></td>
		</tr>
	</tbody>
</table>

combined infusion and stimulation with fast-scan cyclic voltammetry (cis-fscv) to assess ventral tegmental area receptor regulation of phasic dopamine

Phasic dopamine (DA) release from the ventral tegmental area (VTA) to the nucleus accumbens plays a pivotal role in reward processing and reinforcement learning. Understanding how the diverse neuronal inputs into the VTA control phasic DA release can provide a better picture of the circuitry that controls reward processing and reinforcement learning. Here, we describe a method that combines intra-VTA cannula infusions of pharmacological agonists and antagonists with stimulation-evoked phasic DA release (combined infusion and stimulation, or CIS) as measured by in vivo fast-scan cyclic voltammetry (FSCV). Using CIS-FSCV in anesthetized rats, a phasic DA response can be evoked by electrically stimulating the VTA with a bipolar electrode fitted with a cannula while recording in the nucleus accumbens core. Pharmacological agonists or antagonists can be infused directly at the stimulation site to investigate specific VTA receptors&#39; roles in driving phasic DA release. A major benefit of CIS-FSCV is that VTA receptor function can be studied in vivo, building on in vitro studies.

CIS-FSCV was used to study the function of VTA N-methyl-D-aspartate receptors (NMDAR), nicotinic acetylcholine receptors (nAChRs), and muscarinic acetylcholine receptors (mAChRs) in driving phasic DA release in the NAc core. Figure 2 shows representative data for a negative control, infusion of 0.9% saline, before (baseline) and 9 min postinfusion (saline). Figure 2 shows a color plot with potential on the y-axis, time on the x-a...

Watch this Scientific Journal Video about Combined Infusion and Stimulation with Fast-Scan Cyclic Voltammetry CIS-FSCV to Assess Ventral Tegmental Area Receptor Regulation of Phasic Dopamine at JoVE.c

Combined Infusion and Stimulation with Fast-Scan Cyclic Voltammetry CIS-FSCV to Assess Ventral Tegmental Area Receptor Regulation of Phasic Dopamine

The goal of this protocol is to directly manipulate ventral tegmental area receptors to study their contribution to subsecond dopamine release.

Combined Infusion and Stimulation with Fast-Scan Cyclic Voltammetry (CIS-FSCV) to Assess Ventral Tegmental Area Receptor Regulation of Phasic Dopamine

Phasic dopamine (DA) release from the ventral tegmental area (VTA) to the nucleus accumbens plays a pivotal role in reward processing and reinforcement ...

This approach can help elucidate the role of specific ventral tegmental area, somatodendritic receptors and phasic dopamine release in the nucleus accumbens. The main advantage of this approach is that questions about receptor function control over phasic dopamine release can be addressed in the intact brain. Optimizing the carbon fiber microelectrode and bipolar stimulator location can be challenging, and some advice for beginners is starting recording in the dorsal striatum.Due to the use and manipulation of multiple types of electrodes, including recording, reference, and stimulating electrodes, a visual guide of when and where these electrodes are implanted will be useful. After confirming a lack of response to pedal reflex, clean the scalp of an anesthetized rat with three sequential iodopovidone and 70%ethanol scrubs. After the last scrub, use sterilized needle nose tweezers and surgical scissors to cut away enough scalp tissue to make room for the implanted electrodes.Gently clean the exposed skull surface with sterilized cotton tip applicators before applying two to three drops of 3%hydrogen peroxide to help identify lambda and bregma. Next, use a one millimeter drill bit set to approximately 20, 000 revolutions per minute to make a 1.5 millimeter diameter hole, 2.5 millimeters anterior and 3.5 millimeters lateral to the bregma. Implant a 1.59 millimeter outer diameter, 3.2 millimeter long screw about halfway into the hole until the screw is firmly in place.Next, drill a one millimeter diameter reference electrode hole in the left hemisphere, 1.5 millimeters anterior, and 3.5 millimeters lateral to the bregma. Insert approximately two millimeters of reference wire into the hole while wrapping the wire around and under the head of the implanted screw. Then fully implant the screw, pinning the reference electrode in place.In the right hemisphere, drill a 1.5 millimeter diameter hole, 1.2 millimeters anterior, and 1.4 millimeters lateral to the bregma, and use tweezers to carefully remove the dura. For the stimulating electrode, drill a square hole two millimeters anterior-posterior and five millimeters medial-lateral centered at 5.2 millimeters posterior and one millimeter lateral to the bregma. Using stereotactic arm bars, lower the bipolar stimulating electrode guide cannula five millimeters below the dura.Using the stereotactic arm bars, lower the carbon fiber microelectrode four millimeters below the dura at the most dorsal portion of the striatum and connect the reference wire and carbon fiber to a potentiostat. Then apply a minus 0.4 to 1.4 volt, 400 volt per second triangular waveform for 15 minutes at 60 Hertz, followed by a 10-minute stimulus at 10 Hertz. To optimize the stimulating electrode location, set the stimulator to produce a bipolar electrical waveform with a 60 Hertz frequency, 24 pulses, 300 microamp current, and two millisecond per phase pulse width.Gently lower the stimulator in 0.2 millimeter increments from 5 to 7.8 millimeters below the dura, stimulating the VTA at each increment. Continue to lower the bipolar-stimulating electrode guide cannula until a stimulation produces phasic dopamine release at the carbon fiber microelectrode within the dorsal striatum. Once a dopamine release has been observed, lower the carbon fiber microelectrode until it is at least six millimeters below the dura into the most dorsal part of the nucleus accumbens core.When the electrode is in position, stimulate the VTA and record the peak amplitude of the dopamine peak, then lower or raise the carbon fiber microelectrode to the site that produces the greatest dopamine release, making sure that the peak of the dopamine response is represented as a clear oxidation peak at 0.6 volts and a reduction peak at minus 0.2 volts. Once the carbon fiber and stimulating electrode guide cannula location has been optimized, stimulate the animal every three minutes for 20 to 30 minutes. After achieving a stable baseline, gently lower the internal cannula by hand into the guide cannula pre-fitted into the bipolar stimulator and obtain an additional two to three baseline recordings to confirm that the cannula insertion did not cause a change in the evoked signal.Once a baseline response has been established, use a syringe pump and a microsyringe to infuse 0.5 microliters of the drug solution of interest into the VTA over a two-minute period. After the infusion, leave the internal cannula in place for at least one minute prior to removal, continuing to record the response every three minutes to measure the post-infusion effects. As demonstrated in these representative color plots, saline infusion does not alter the stimulated phasic dopamine release.The infusion of NMDA produces a robust increase in stimulated phasic dopamine release, while the NMDA receptor competitive antagonist, AP5, produces a robust decrease. Both the non-competitive nicotinic acetylcholine receptor antagonist mecamylamine and the non-selective competitive muscarinic acetylcholine receptor antagonist scopolamine produce a robust decrease in the stimulated phasic dopamine release. In this graph, a summary of the effects of the tested drugs over time can be observed.The infusion cannula must be carefully inserted into the bipolar stimulating electrode. Otherwise, excessive damage can occur, leading to artifactual changes in phasic dopamine release. This approach has allowed investigators to more finely address the specific receptor mechanisms by which phasic dopamine release is regulated in vivo.

combined-infusion-stimulation-with-fast-scan-cyclic-voltammetry-cis

Research

JoVE Journal

Neuroscience

Combining Transcranial Magnetic Stimulation and fMRI to Examine the Default Mode Network

The default mode network is a group of brain regions that are active when an individual is not focused on the outside world and the brain is at "wakeful rest."1,2,3 It is thought the default mode network corresponds to self-referential or "internal mentation".2,3
It has been hypothesized that, in humans, activity within the default mode network is correlated with certain pathologies (for instance, hyper-activation has been linked to schizophrenia 4,5,6 and autism spectrum disorders 7 whilst hypo-activation of the network has been linked to Alzheimer's and other neurodegenerative diseases 8). As such, noninvasive modulation of this network may represent a potential therapeutic intervention for a number of neurological and psychiatric pathologies linked to abnormal network activation. One possible tool to effect this modulation is Transcranial Magnetic Stimulation: a non-invasive neurostimulatory and neuromodulatory technique that can transiently or lastingly modulate cortical excitability (either increasing or decreasing it) via the application of localized magnetic field pulses.9
In order to explore the default mode network's propensity towards and tolerance of modulation, we will be combining TMS (to the left inferior parietal lobe) with functional magnetic resonance imaging (fMRI). Through this article, we will examine the protocol and considerations necessary to successfully combine these two neuroscientific tools.

In this article, we examine the methodology and considerations relevant to the combination of TMS and fMRI to examine the effects of brain stimulation on the default network.

The default mode network is a group of brain regions that are active when an individual is not focused on the outside world and the brain is at "wakeful ...

TMS: Using the Theta-Burst Protocol to Explore Mechanism of Plasticity in Individuals with Fragile X Syndrome and Autism

Fragile X Syndrome (FXS), also known as Martin-Bell Syndrome, is a genetic abnormality found on the X chromosome.1,2 Individuals suffering from FXS display abnormalities in the expression of FMR1 - a protein required for typical, healthy neural development.3 Recent data has suggested that the loss of this protein can cause the cortex to be hyperexcitable thereby affecting overall patterns of neural plasticity.4,5
In addition, Fragile X shows a strong comorbidity with autism: in fact, 30% of children with FXS are diagnosed with autism, and 2 - 5% of autistic children suffer from FXS.6
Transcranial Magnetic Stimulation (a non-invasive neurostimulatory and neuromodulatory technique that can transiently or lastingly modulate cortical excitability via the application of localized magnetic field pulses 7,8) represents a unique method of exploring plasticity and the manifestations of FXS within affected individuals. More specifically, Theta-Burst Stimulation (TBS), a specific stimulatory protocol shown to modulate cortical plasticity for a duration up to 30 minutes after stimulation cessation in healthy populations, has already proven an efficacious tool in the exploration of abnormal plasticity.9,10 
Recent studies have shown the effects of TBS last considerably longer in individuals on the autistic spectrum - up to 90 minutes.11 This extended effect-duration suggests an underlying abnormality in the brain's natural plasticity state in autistic individuals - similar to the hyperexcitability induced by Fragile X Syndrome.
In this experiment, utilizing single-pulse motor-evoked potentials (MEPs) as our benchmark, we will explore the effects of both intermittent and continuous TBS on cortical plasticity in individuals suffering from FXS and individuals on the Autistic Spectrum.

In this article, we examine the effects of Theta-Burst TMS stimulation on cortical plasticity in individuals suffering from Fragile X syndrome and individuals on the autistic spectrum.

Fragile X Syndrome (FXS), also known as Martin-Bell Syndrome, is a genetic abnormality found on the X chromosome.1,2 Individuals suffering from FXS ...

Presynaptic Dopamine Dynamics in Striatal Brain Slices with Fast-scan Cyclic Voltammetry

Extensive research has focused on the neurotransmitter dopamine because of its importance in the mechanism of action of drugs of abuse (e.g. cocaine and amphetamine), the role it plays in psychiatric illnesses (e.g. schizophrenia and Attention Deficit Hyperactivity Disorder), and its involvement in degenerative disorders like Parkinson's and Huntington's disease. Under normal physiological conditions, dopamine is known to regulate locomotor activity, cognition, learning, emotional affect, and neuroendocrine hormone secretion. One of the largest densities of dopamine neurons is within the striatum, which can be divided in two distinct neuroanatomical regions known as the nucleus accumbens and the caudate-putamen. The objective is to illustrate a general protocol for slice fast-scan cyclic voltammetry (FSCV) within the mouse striatum. FSCV is a well-defined electrochemical technique providing the opportunity to measure dopamine release and uptake in real time in discrete brain regions. Carbon fiber microelectrodes (diameter of ~ 7 &mu;m) are used in FSCV to detect dopamine oxidation. The analytical advantage of using FSCV to detect dopamine is its enhanced temporal resolution of 100 milliseconds and spatial resolution of less than ten microns, providing complementary information to in vivo microdialysis.

Using fast-scan cyclic voltammetry to measure electrically evoked presynaptic dopamine dynamics in striatal brain slices.

Extensive research has focused on the neurotransmitter dopamine because of its importance in the mechanism of action of drugs of abuse (e.g. cocaine and ...

Voltage Biasing, Cyclic Voltammetry, &amp; Electrical Impedance Spectroscopy for Neural Interfaces

Electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measure properties of the electrode-tissue interface without additional invasive procedures, and can be used to monitor electrode performance over the long term. EIS measures electrical impedance at multiple frequencies, and increases in impedance indicate increased glial scar formation around the device, while cyclic voltammetry measures the charge carrying capacity of the electrode, and indicates how charge is transferred at different voltage levels. As implanted electrodes age, EIS and CV data change, and electrode sites that previously recorded spiking neurons often exhibit significantly lower efficacy for neural recording. The application of a brief voltage pulse to implanted electrode arrays, known as rejuvenation, can bring back spiking activity on otherwise silent electrode sites for a period of time. Rejuvenation alters EIS and CV, and can be monitored by these complementary methods. Typically, EIS is measured daily as an indication of the tissue response at the electrode site. If spikes are absent in a channel that previously had spikes, then CV is used to determine the charge carrying capacity of the electrode site, and rejuvenation can be applied to improve the interface efficacy. CV and EIS are then repeated to check the changes at the electrode-tissue interface, and neural recordings are collected. The overall goal of rejuvenation is to extend the functional lifetime of implanted arrays.

The electrode-tissue interface of neural recording electrodes can be characterized with electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Application of voltage biasing changes the electrochemical properties of the electrode-tissue interface and can improve recording capability. Voltage biasing, EIS, CV, and neural recordings are complementary.

Electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measure properties of the electrode-tissue interface without additional invasive ...

Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry

After its release into the synaptic cleft, dopamine exerts its biological properties via its pre- and post-synaptic targets1. The dopamine signal is terminated by diffusion2-3, extracellular enzymes4, and membrane transporters5. The dopamine transporter, located in the peri-synaptic cleft of dopamine neurons clears the released amines through an inward dopamine flux (uptake). The dopamine transporter can also work in reverse direction to release amines from inside to outside in a process called outward transport or efflux of dopamine5. More than 20 years ago Sulzer et al. reported the dopamine transporter can operate in two modes of activity: forward (uptake) and reverse (efflux)5. The neurotransmitter released via efflux through the transporter can move a large amount of dopamine to the extracellular space, and has been shown to play a major regulatory role in extracellular dopamine homeostasis6. Here we describe how simultaneous patch clamp and amperometry recording can be used to measure released dopamine via the efflux mechanism with millisecond time resolution when the membrane potential is controlled. For this, whole-cell current and oxidative (amperometric) signals are measured simultaneously using an Axopatch 200B amplifier (Molecular Devices, with a low-pass Bessel filter set at 1,000 Hz for whole-cell current recording). For amperometry recording a carbon fiber electrode is connected to a second amplifier (Axopatch 200B) and is placed adjacent to the plasma membrane and held at +700 mV. The whole-cell and oxidative (amperometric) currents can be recorded and the current-voltage relationship can be generated using a voltage step protocol. Unlike the usual amperometric calibration, which requires conversion to concentration, the current is reported directly without considering the effective volume7. Thus, the resulting data represent a lower limit to dopamine efflux because some transmitter is lost to the bulk solution.

The amperometric technique measures dopamine release from a single cell by detecting the oxidative current produced by spontaneous dopamine oxidization. Simultaneous voltage clamp and amperometry methodology reveal the mechanistic relationship between the overall "activity" of dopamine transporter and the regulatory role of this activity on the reverse transport of dopamine.

After its release into the synaptic cleft, dopamine exerts its biological properties via its pre- and post-synaptic targets1. The dopamine signal is ...

Comprehensive Profiling of Dopamine Regulation in Substantia Nigra and Ventral Tegmental Area

Dopamine is a vigorously studied neurotransmitter in the CNS. Indeed, its involvement in locomotor activity and reward-related behaviour has fostered five decades of inquiry into the molecular deficiencies associated with dopamine regulation. The majority of these inquiries of dopamine regulation in the brain focus upon the molecular basis for its regulation in the terminal field regions of the nigrostriatal and mesoaccumbens pathways; striatum and nucleus accumbens. Furthermore, such studies have concentrated on analysis of dopamine tissue content with normalization to only wet tissue weight. Investigation of the proteins that regulate dopamine, such as tyrosine hydroxylase (TH) protein, TH phosphorylation, dopamine transporter (DAT), and vesicular monoamine transporter 2 (VMAT2) protein often do not include analysis of dopamine tissue content in the same sample. The ability to analyze both dopamine tissue content and its regulating proteins (including post-translational modifications) not only gives inherent power to interpreting the relationship of dopamine with the protein level and function of TH, DAT, or VMAT2, but also extends sample economy. This translates into less cost, and yet produces insights into the molecular regulation of dopamine in virtually any paradigm of the investigators' choice.
We focus the analyses in the midbrain. Although the SN and VTA are typically neglected in most studies of dopamine regulation, these nuclei are easily dissected with practice. A comprehensive readout of dopamine tissue content and TH, DAT, or VMAT2 can be conducted. There is burgeoning literature on the impact of dopamine function in the SN and VTA on behavior, and the impingements of exogenous substances or disease processes therein 1-5. Furthermore, compounds such as growth factors have a profound effect on dopamine and dopamine-regulating proteins, to a comparatively greater extent in the SN or VTA 6-8. Therefore, this methodology is presented for reference to laboratories that want to extend their inquiries on how specific treatments modulate behaviour and dopamine regulation. Here, a multi-step method is presented for the analyses of dopamine tissue content, the protein levels of TH, DAT, or VMAT2, and TH phosphorylation from the substantia nigra and VTA from rodent midbrain. The analysis of TH phosphorylation can yield significant insights into not only how TH activity is regulated, but also the signaling cascades affected in the somatodendritic nuclei in a given paradigm.
We will illustrate the dissection technique to segregate these two nuclei and the sample processing of dissected tissue that produces a profile revealing molecular mechanisms of dopamine regulation in vivo, specific for each nuclei (Figure 1).

Dopamine is distinctly regulated in the midbrain nuclei, which contain the cell bodies and dendrites of the dopamine neurons. Here we describe a dissection and sample-handling approach to maximize results, and thus conclusions and insights, on dopamine regulation in the midbrain nuclei of the substantia nigra (SN) and ventral tegmental area (VTA) in rodents.

Dopamine is a vigorously studied neurotransmitter in the CNS. Indeed, its involvement in locomotor activity and reward-related behaviour has fostered five ...

Laser Capture Microdissection - A Demonstration of the Isolation of Individual Dopamine Neurons and the Entire Ventral Tegmental Area

Laser capture microdissection (LCM) is used to isolate a concentrated population of individual cells or precise anatomical regions of tissue from tissue sections on a microscope slide. When combined with immunohistochemistry, LCM can be used to isolate individual cells types based on a specific protein marker. Here, the LCM technique is described for collecting a specific population of dopamine neurons directly labeled with&#160;tyrosine hydroxylase immunohistochemistry and for isolation of the dopamine neuron containing region of the ventral tegmental area using indirect tyrosine hydroxylase immunohistochemistry on a section adjacent to those used for LCM. An infrared (IR) capture laser is used to both dissect individual neurons as well as the ventral tegmental area off glass slides and onto an LCM cap for analysis. Complete dehydration of the tissue with 100% ethanol and xylene is critical. The combination of the IR capture laser and the ultraviolet (UV) cutting laser is used to isolate individual dopamine neurons or the ventral tegmental area when using PEN membrane slides. A PEN membrane slide has significant advantages over a glass slide as it offers better consistency in capturing and collecting cells, is faster collecting large pieces of tissue, is less reliant on dehydration and results in complete removal of the tissue from the slide. Although removal of large areas of tissue from a glass slide is feasible, it is considerably more time consuming and frequently leaves some residual tissue behind. Data shown here demonstrate that RNA of sufficient quantity and quality can be obtained using these procedures for quantitative PCR measurements. Although RNA and DNA are the most commonly isolated molecules from tissue and cells collected with LCM, isolation and measurement of microRNA, protein and epigenetic changes in DNA can also benefit from the enhanced anatomical and cellular resolution obtained using LCM.

The isolation of individual dopamine neurons or the ventral tegmental area with direct or indirect immunohistochemistry is demonstrated using laser capture microdissection. Parameters for isolation of tissue from a glass slide using an infrared laser and from membrane slides using the combination of an infrared and ultraviolet laser are discussed.

Laser capture microdissection (LCM) is used to isolate a concentrated population of individual cells or precise anatomical regions of tissue from tissue ...

The Preparation of Oblique Spinal Cord Slices for Ventral Root Stimulation

Electrophysiological recordings from spinal cord slices have proven to be a valuable technique to investigate a wide range of questions, from cellular to network properties. We show how to prepare viable oblique slices of the spinal cord of young mice (P2 - P11). In this preparation, the motoneurons retain&#160;their axons coming out from the ventral roots of the&#160;spinal cord. Stimulation of these axons elicits back-propagating action potentials invading the motoneuron&#160;somas and exciting the motoneuron&#160;collaterals within the spinal cord. Recording of antidromic action potentials is an immediate, definitive and elegant way to characterize motoneuron identity, which surpasses&#160;other identification methods. Furthermore, stimulating the motoneuron collaterals is a simple and reliable way to excite the collateral targets of the motoneurons within the spinal cord, such as other motoneurons or Renshaw cells. In this protocol, we present antidromic recordings from the motoneuron somas as well as Renshaw cell excitation, resulting from ventral root stimulation.

We show how to prepare oblique slices of the spinal cord in young mice. This preparation allows for the stimulation of the ventral roots.

Electrophysiological recordings from spinal cord slices have proven to be a valuable technique to investigate a wide range of questions, from cellular to ...

Using Enzyme-based Biosensors to Measure Tonic and Phasic Glutamate in Alzheimer's Mouse Models

Neurotransmitter disruption is often a key component of diseases of the central nervous system (CNS), playing a role in the pathology underlying Alzheimer's disease, Parkinson's disease, depression, and anxiety. Traditionally, microdialysis has been the most common (lauded) technique to examine neurotransmitter changes that occur in these disorders. But because microdialysis has the ability to measure slow 1-20 minute changes across large areas of tissue, it has the disadvantage of invasiveness, potentially destroying intrinsic connections within the brain and a slow sampling capability. A relatively newer technique, the microelectrode array (MEA), has numerous advantages for measuring specific neurotransmitter changes within discrete brain regions as they occur, making for a spatially and temporally precise approach. In addition, using MEAs is minimally invasive, allowing for measurement of neurotransmitter alterations in vivo. In our laboratory, we have been specifically interested in changes in the neurotransmitter, glutamate, related to Alzheimer's disease pathology. As such, the method described here has been used to assess potential hippocampal disruptions in glutamate in a transgenic mouse model of Alzheimer's disease. Briefly, the method used involves coating a multi-site microelectrode with an enzyme very selective for the neurotransmitter of interest and using self-referencing sites to subtract out background noise and interferents. After plating and calibration, the MEA can be constructed with a micropipette and lowered into the brain region of interest using a stereotaxic device. Here, the method described involves anesthetizing rTg(TauP301L)4510 mice and using a stereotaxic device to precisely target sub-regions (DG, CA1, and CA3) of the hippocampus.

Using Enzyme-based Biosensors to Measure Tonic and Phasic Glutamate in Alzheimer&#039;s Mouse Models

Here, we describe the setup, software navigation, and data analysis for a spatially and temporally precise method of measuring tonic and phasic extracellular glutamate changes in vivo using enzyme-linked microelectrode arrays (MEA).

Neurotransmitter disruption is often a key component of diseases of the central nervous system (CNS), playing a role in the pathology underlying ...

Modeling Fast-scan Cyclic Voltammetry Data from Electrically Stimulated Dopamine Neurotransmission Data Using QNsim1.0

Central dopaminergic (DAergic) pathways have an important role in a wide range of functions, such as attention, motivation, and movement. Dopamine (DA) is implicated in diseases and disorders including attention deficit hyperactivity disorder, Parkinson's disease, and traumatic brain injury. Thus, DA neurotransmission and the methods to study it are of intense scientific interest. In vivo fast-scan cyclic voltammetry (FSCV) is a method that allows for selectively monitoring DA concentration changes with fine temporal and spatial resolution. This technique is commonly used in conjunction with electrical stimulations of ascending DAergic pathways to control the impulse flow of dopamine neurotransmission. Although the stimulated DA neurotransmission paradigm can produce robust DA responses with clear morphologies, making them amenable for kinetic analysis, there is still much debate on how to interpret the responses in terms of their DA release and clearance components. To address this concern, a quantitative neurobiological (QN) framework of stimulated DA neurotransmission was recently developed to realistically model the dynamics of DA release and reuptake over the course of a stimulated DA response. The foundations of this model are based on experimental data from stimulated DA neurotransmission and on principles of neurotransmission adopted from various lines of research. The QN model implements 12 parameters related to stimulated DA release and reuptake dynamics to model DA responses. This work describes how to simulate DA responses using QNsim1.0 and also details principles that have been implemented to systematically discern alterations in the stimulated dopamine release and reuptake dynamics.

Fast-scan cyclic voltammetry can monitor in vivo dopamine neurotransmission in the context of drugs, disease, and other experimental manipulations. This work describes the implementation of QNsim1.0, a software to model electrically stimulated dopamine responses according to the quantitative neurobiological model to quantify estimates of dopamine release and reuptake dynamics.

Central dopaminergic (DAergic) pathways have an important role in a wide range of functions, such as attention, motivation, and movement. Dopamine (DA) is ...