We would like to thank Ms. Rui Chen for the dissection and images of the Drosophila CNS shown in the figures.

1. Equipment and Materials
<ol>
	<li>Prepare the required components (listed in Table of Materials) of the electrophysiology rig to perform suction electrode recordings of the Drosophila CNS. 
	NOTE: Prior to experimentation, it is necessary to construct chambers for dissection of the Drosophila CNS and to be used for bathing the ganglia in saline during recordings. A step-by-step outline of chamber construction is provided below.</li>
	<li>Prepare the larval chamber.
	<ol>
		<li...

<ol>
	<li>Sparks, T. C., Nauen, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=IRAC:+Mode+of+action+classification+and+insecticide+resistance+management.">IRAC: Mode of action classification and insecticide resistance management.</a> Pesticide Biochemistry and Physiology. 121, 122-128 (2015).</li><li>Swale, D. 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=An+insecticide+resistance-breaking+mosquitocide+targeting+inward+rectifier+potassium+channels+in+vectors+of+Zika+virus+and+malaria.">An insecticide resistance-breaking mosquitocide targeting inward rectifier potassium channels in vectors of Zika virus and malaria.</a> Scientific Reports. 6, 36954 (2016).</li><li>Troczka, B. 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=Stable+expression+and+functional+characterisation+of+the+diamondback+moth+ryanodine+receptor+G4946E+variant+conferring+resistance+to+diamide+insecticides.">Stable expression and functional characterisation of the diamondback moth ryanodine receptor G4946E variant conferring resistance to diamide insecticides.</a> Scientific Reports. 5, 14680 (2015).</li><li>Bloomquist, J. 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=Voltage-sensitive+potassium+KV2+channels+as+new+targets+for+insecticides.">Voltage-sensitive potassium KV2 channels as new targets for insecticides.</a> Biopesticides: State of the Art and Future Opportunities. 1172, 71-81 (2014).</li><li>Jenson, L. J., Bloomquist, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+serum+and+ion+channel+block+on+growth+and+hormonally-induced+differentiation+of+Spodoptera+frugiperda+(Sf21)+insect+cells.">Role of serum and ion channel block on growth and hormonally-induced differentiation of Spodoptera frugiperda (Sf21) insect cells.</a> Archives of Insect Biochemistry and Physiology. 90 (3), 131-139 (2015).</li><li>Jenson, L. J., Sun, B., Bloomquist, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Voltage-sensitive+potassium+channels+expressed+after+20-Hydroxyecdysone+treatment+of+a+mosquito+cell+line.">Voltage-sensitive potassium channels expressed after 20-Hydroxyecdysone treatment of a mosquito cell line.</a> Insect Biochemistry and Molecular Biolology. 87, 75-80 (2017).</li><li>Chintapalli, V. R., Wang, J., Dow, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+FlyAtlas+to+identify+better+Drosophila+melanogaster+models+of+human+disease.">Using FlyAtlas to identify better Drosophila melanogaster models of human disease.</a> Nature Genetics. 39 (6), 715-720 (2007).</li><li>Duffy, J. 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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=Larvalign:+Aligning+gene+expression+patterns+from+the+larval+brain+of+Drosophila+melanogaster.">Larvalign: Aligning gene expression patterns from the larval brain of Drosophila melanogaster.</a> Neuroinformatics. 16 (1), 65-80 (2017).</li><li>Sprecher, S. G., Reichert, H., Hartenstein, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+expression+patterns+in+primary+neuronal+clusters+of+the+Drosophila+embryonic+brain.">Gene expression patterns in primary neuronal clusters of the Drosophila embryonic brain.</a> Gene Expression Patterns. 7 (5), 584-595 (2007).</li><li>Zhou, S., 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=A+Drosophila+model+for+toxicogenomics:+Genetic+variation+in+susceptibility+to+heavy+metal+exposure.">A Drosophila model for toxicogenomics: Genetic variation in susceptibility to heavy metal exposure.</a> PLoS Genetics. 13 (7), e1006907 (2017).</li><li>Manev, H., Dimitrijevic, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+model+for+in+vivo+pharmacological+analgesia+research.">Drosophila model for in vivo pharmacological analgesia research.</a> European Journal of Pharmacology. 491 (2-3), 207-208 (2004).</li><li>Pandey, U. B., Nichols, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+disease+models+in+Drosophila+melanogaster+and+the+role+of+the+fly+in+therapeutic+drug+discovery.">Human disease models in Drosophila melanogaster and the role of the fly in therapeutic drug discovery.</a> Pharmacological Reviews. 63 (2), 411-436 (2011).</li><li>Hekmat-Scafe, D. S., Lundy, M. Y., Ranga, R., Tanouye, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutations+in+the+K+/Cl-+cotransporter+gene+kazachoc+(kcc)+increase+seizure+susceptibility+in+Drosophila.">Mutations in the K+/Cl- cotransporter gene kazachoc (kcc) increase seizure susceptibility in Drosophila.</a> Journal of Neuroscience. 26 (35), 8943-8954 (2006).</li><li>Whitworth, A. 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=Increased+glutathione+S-transferase+activity+rescues+dopaminergic+neuron+loss+in+a+Drosophila+model+of+Parkinson's+disease.">Increased glutathione S-transferase activity rescues dopaminergic neuron loss in a Drosophila model of Parkinson's disease.</a> Proceedings of the National Academy of Science of the United States of America. 102 (22), 8024-8029 (2005).</li><li>Watson, M. R., Lagow, R. D., Xu, K., Zhang, B., Bonini, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Drosophila+model+for+amyotrophic+lateral+sclerosis+reveals+motor+neuron+damage+by+human+SOD1.">A Drosophila model for amyotrophic lateral sclerosis reveals motor neuron damage by human SOD1.</a> Journal of Biological Chemistry. 283 (36), 24972-24981 (2008).</li><li>Rajendra, T. K., 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=A+Drosophila+melanogaster+model+of+spinal+muscular+atrophy+reveals+a+function+for+SMN+in+striated+muscle.">A Drosophila melanogaster model of spinal muscular atrophy reveals a function for SMN in striated muscle.</a> Journal of Cell Biology. 176 (6), 831-841 (2007).</li><li>Chan, H. Y., Bonini, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+models+of+human+neurodegenerative+disease.">Drosophila models of human neurodegenerative disease.</a> Cell Death and Differentiation. 7 (11), 1075-1080 (2000).</li><li>Limmer, S., Weiler, A., Volkenhoff, A., Babatz, F., Klambt, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Drosophila+blood-brain+barrier:+development+and+function+of+a+glial+endothelium.">The Drosophila blood-brain barrier: development and function of a glial endothelium.</a> Frontiers in Neuroscience. 8, 365 (2014).</li><li>Rickert, C., Kunz, T., Harris, K. L., Whitington, P. M., Technau, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+characterization+of+the+entire+interneuron+population+reveals+principles+of+neuromere+organization+in+the+ventral+nerve+cord+of+Drosophila.">Morphological characterization of the entire interneuron population reveals principles of neuromere organization in the ventral nerve cord of Drosophila.</a> Journal of Neuroscience. 31 (44), 15870-15883 (2011).</li><li>Schwabe, T., Li, X., Gaul, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+analysis+of+the+mesenchymal-epithelial+transition+of+blood-brain+barrier+forming+glia+in+Drosophila.">Dynamic analysis of the mesenchymal-epithelial transition of blood-brain barrier forming glia in Drosophila.</a> Biology Open. 6 (2), 232-243 (2017).</li><li>Abbott, N. J., Ronnback, L., Hansson, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Astrocyte-endothelial+interactions+at+the+blood-brain+barrier.">Astrocyte-endothelial interactions at the blood-brain barrier.</a> Nature Reviews Neuroscience. 7 (1), 41-53 (2006).</li><li>Abbott, N. J., Dolman, D. E., Patabendige, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assays+to+predict+drug+permeation+across+the+blood-brain+barrier,+and+distribution+to+brain.">Assays to predict drug permeation across the blood-brain barrier, and distribution to brain.</a> Current Drug Metabolism. 9 (9), 901-910 (2008).</li><li>Swale, D. R., Sun, B., Tong, F., Bloomquist, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurotoxicity+and+mode+of+action+of+N,+N-diethyl-meta-toluamide+(DEET).">Neurotoxicity and mode of action of N, N-diethyl-meta-toluamide (DEET).</a> PLoS One. 9 (8), e103713 (2014).</li><li>Hafer, N., Schedl, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissection+of+larval+CNS+in+Drosophila+melanogaster.">Dissection of larval CNS in Drosophila melanogaster.</a> Journal of Visualized Experiments. (1), 85 (2006).</li><li>Bloomquist, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mode+of+action+of+atracotoxin+at+central+and+peripheral+synapses+of+insects.">Mode of action of atracotoxin at central and peripheral synapses of insects.</a> Invertebrate Neuroscience. 5 (1), 45-50 (2003).</li><li>Bloomquist, J. R., Roush, R. T., ffrench-Constant, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduced+neuronal+sensitivity+to+dieldrin+and+picrotoxinin+in+a+cyclodiene-resistant+strain+of+Drosophila+melanogaster+(Meigen).">Reduced neuronal sensitivity to dieldrin and picrotoxinin in a cyclodiene-resistant strain of Drosophila melanogaster (Meigen).</a> Archives of Insect Biochemistry and Physiology. 19 (1), 17-25 (1992).</li><li>Mutunga, J. 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=Neurotoxicology+of+bis(n)-tacrines+on+Blattella+germanica+and+Drosophila+melanogaster+acetylcholinesterase.">Neurotoxicology of bis(n)-tacrines on Blattella germanica and Drosophila melanogaster acetylcholinesterase.</a> Archives of Insect Biochemistry and Physiology. 83 (4), 180-194 (2013).</li><li>Chen, R., Swale, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inwardly+rectifying+potassium+(Kir)+channels+represent+a+critical+ion+conductance+pathway+in+the+nervous+systems+of+insects.">Inwardly rectifying potassium (Kir) channels represent a critical ion conductance pathway in the nervous systems of insects.</a> Scientific Reports. 8 (1), 1617 (2018).</li><li>Francis, S. A., Taylor-Wells, J., Gross, A. D., Bloomquist, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxicity+and+physiological+actions+of+carbonic+anhydrase+inhibitors+to+Aedes+aegypti+and+Drosophila+melanogaster.">Toxicity and physiological actions of carbonic anhydrase inhibitors to Aedes aegypti and Drosophila melanogaster.</a> Insects. 8 (1), 2 (2016).</li><li>Swale, D. 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The details provided in the associated video and text have provided key steps in order to record the activity and spike discharge frequency of the Drosophila CNS ex vivo. The dissection efficacy is the most critical aspect of the method because short or few descending neurons will reduce the baseline firing rate that will result in large variances between replicates. However, once the dissection technique has been mastered, the data collected with this assay are highly reproducible and amendable for a w...

The overall goal of this approach is to enable researchers to quickly measure the electrogenesis of the central nervous system (CNS) in the model insect, Drosophila melanogaster. This method is reliable, quick, and cost-efficient to perform physiological and toxicological experimentation. The CNS is essential for life and therefore, the physiological pathways critical for proper neural function have been explored extensively in an effort to understand or modify neural function. Characterization of the signaling pathways within the arthropod CNS has enabled the discovery of several chemical classes of insecticides that disrupt invertebrate neural function to induce mortality while limiting off-target consequences. Thus, the ability to measure the neural activity of insects is of significant interest to the field of insect toxicology and physiology since the nervous system is the target tissue of the majority of deployed insecticides1. Yet, continued growth of fundamental and applied knowledge regarding the insect nervous system requires advanced neurophysiological techniques that are limited in feasibility, since current techniques are labor intensive and require a high expense, insect neural cell lines are limited, and/or there is limited access to the central synapses of most arthropods. Currently, characterization of most insect neural proteins requires the target to be cloned and heterologously expressed for subsequent drug discovery and electrophysiological recordings, as was described for insect inward rectifier potassium channels2, insect ryanodine receptor3, mosquito voltage-sensitive K+ channels4, and others. To mitigate the requirement for heterologous expression and the potential for low functional expression, Bloomquist and colleagues aimed to induce a neuronal phenotype in cultured Spodoptera frugiperda (Sf21) cells as a novel method for insecticide discovery5,6. These methods provide a valid approach for the development of new chemistry, yet they oftentimes create an insurmountable bottleneck for the characterization of pharmacological agents, identifying mechanisms of insecticide resistance, and characterization of fundamental physiological principles. Here, we describe an ex vivo method that enables the recording of electrical activity from a model insect that has malleable genetics7,8,9 and known expression patterns of neural complexes10,11,12 to enable the characterization of resistance mechanisms at the level of the nerve, the mode of action of newly developed drugs, and other toxicological studies.
The fruit fly, D. melanogaster, is a common model organism for defining insect neural systems or insecticide mechanism of action and has been established as a well-suited model organism for the study of toxicological13, pharmacological14,15, neurophysiological16, and pathophysiological17,18,19,20 processes of vertebrates. D.melanogaster is a holometabolous insect that performs complete metamorphosis, including a larval and pupal stage before reaching the reproductive adult stage. Throughout the developmental process, the nervous system undergoes significant remodeling at different life stages, but the larval CNS will be the focus of this methodology. The fully developed larval CNS is anatomically simple with thoracic and abdominal segments that are fused and form the ventral ganglion, which represents an array of repeated and almost identical neuromeric units21,22. Descending motor nerves originate from the caudal end of the subesophageal ganglia and descend to innervate body wall muscles and visceral organs of the larvae. Figure 1 describes the gross anatomy of the larval Drosophila CNS.
The Drosophila blood-brain barrier (BBB) develops at the end of embryogenesis and is formed by subperineurial glial cells (SPG)21. The SPG cells form numerous filopodia-like processes that spread out to establish a contiguous, very flat, endothelial-like sheet that covers the entire Drosophila CNS23. The Drosophila BBB has similarities to the vertebrate BBB, which includes preserving the homeostasis of the neural microenvironment by controlling the entry of nutrients and xenobiotics into the CNS21. This is a prerequisite for reliable neural transmission and function, yet the protection of the CNS by the BBB restricts the permeation of synthetic drugs, most peptides, and other xenobiotics24,25, which introduces potential problems when characterizing potencies of small-molecule modulators. The method uses a simple transection to disrupt this barrier and provide ready pharmacological access to the central synapses. 
The greatest strength of the described methodology is the simplicity, reproducibility, and relatively high-throughput capacity inherent to this system. The protocol is relatively easy to master, the setup requires little space, and only an initial financial input is necessary which is reduced to reagents and consumables. Further, the described method is completely amendable to record the central descending nerve activity of the house fly, Musca domestica26.

<table>
	<tbody>
		<tr>
			<td>Drosophila melanogaster (strain OR)</td>
			<td>Bloomington Drosophila Stock Center</td>
			<td>2376</td>
			<td></td>
		</tr>
		<tr>
			<td>Vibration isolation table</td>
			<td>Kinetic Systems</td>
			<td>9200 series</td>
			<td></td>
		</tr>
		<tr>
			<td>Faraday Cage</td>
			<td>Kinetic Systems</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Dissecting Microscope on a Boom</td>
			<td>Nikon</td>
			<td>SMZ800N</td>
			<td>Multiple scopes can be used; boom stand is critical</td>
		</tr>
		<tr>
			<td>AC/DC differential amplifier</td>
			<td>ADInstruments</td>
			<td>AM3000H</td>
			<td>The model 1700 can be used instead of the model 3000</td>
		</tr>
		<tr>
			<td>audio monitor</td>
			<td>ADInstruments</td>
			<td>AM3300</td>
			<td></td>
		</tr>
		<tr>
			<td>Hum Bug Noise Eliminator</td>
			<td>A-M Systems</td>
			<td>726300</td>
			<td></td>
		</tr>
		<tr>
			<td>Data Acquisition System (PowerLab)</td>
			<td>ADInstruments</td>
			<td>PL3504</td>
			<td>Multiple PowerLab models can be used.</td>
		</tr>
		<tr>
			<td>Lab Chart Pro Software</td>
			<td>ADInstruments</td>
			<td>N/A - Online Download</td>
			<td></td>
		</tr>
		<tr>
			<td>Fiber Optic Lights</td>
			<td>Edmund Optics</td>
			<td>89-740</td>
			<td>Different light sources can be used, but fiber optics are the most adaptable</td>
		</tr>
		<tr>
			<td>Micromanipulator</td>
			<td>World Precision Instruments</td>
			<td>M325</td>
			<td></td>
		</tr>
		<tr>
			<td>Microelectrode Holder</td>
			<td>World Precision Instruments</td>
			<td>MEH715</td>
			<td>Different models are acceptable</td>
		</tr>
		<tr>
			<td>BNC cables</td>
			<td>World Precision Instruments</td>
			<td>multiple based on size</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass Capillaries</td>
			<td>World Precision Instruments</td>
			<td>PG52151-4</td>
			<td></td>
		</tr>
		<tr>
			<td>Microelectrode Puller</td>
			<td>Sutter Instruments</td>
			<td>P-1000</td>
			<td>Also can use Narashige PC-100</td>
		</tr>
		<tr>
			<td>Black Wax</td>
			<td>Carolina Biological Supply</td>
			<td>974228</td>
			<td></td>
		</tr>
		<tr>
			<td>Non-coated insect pins, size #2</td>
			<td>Bioquip</td>
			<td>1208S2</td>
			<td></td>
		</tr>
		<tr>
			<td>Fince Forceps</td>
			<td>Fine Science Tools</td>
			<td>11254-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Vannas Spring Scissors</td>
			<td>Fine Science Tools</td>
			<td>15000-03</td>
			<td></td>
		</tr>
	</tbody>
</table>

electrophysiological recording of the central nervous system activity of third-instar drosophila melanogaster

The majority of the currently available insecticides target the nervous system and genetic mutations of invertebrate neural proteins oftentimes yield deleterious consequences, yet the current methods for recording nervous system activity of an individual animal is costly and laborious. This suction electrode preparation of the third-instar larval central nervous system of Drosophila melanogaster, is a tractable system for testing the physiological effects of neuroactive agents, determining the physiological role of various neural pathways to CNS activity, as well as the influence of genetic mutations to neural function. This ex vivo preparation requires only moderate dissecting skill and electrophysiological expertise to generate reproducible recordings of insect neuronal activity. A wide variety of chemical modulators, including peptides, can then be applied directly to the nervous system in solution with the physiological saline to measure the influence on the CNS activity. Further, genetic technologies, such as the GAL4/UAS system, can be applied independently or in tandem with pharmacological agents to determine the role of specific ion channels, transporters, or receptors to arthropod CNS function. In this context, the assays described herein are of significant interest to insecticide toxicologists, insect physiologists, and developmental biologists for which D. melanogaster is an established model organism. The goal of this protocol is to describe an electrophysiological method to enable the measurement of electrogenesis of the central nervous system in the model insect, Drosophila melanogaster, which is useful for testing a diversity of scientific hypotheses.

Spontaneous activity of the descending peripheral nerves arising from the Drosophila central nervous system can be recorded using extracellular suction electrodes with consistent reproducibility. Spontaneous activity of the excised and transected Drosophila CNS produces a cyclical pattern of bursting with 1-2 s of firing with approximately 1 s of near quiescent activity. For example, the CNS is near quiescent (1-2 Hz) for 0.5-1 s, followed by a burst (100-400 Hz) for app...

Watch this Scientific Journal Video about Electrophysiological Recording of The Central Nervous System Activity of Third-Instar  Drosophila Melanogaster at JoVE.com

Electrophysiological Recording of The Central Nervous System Activity of Third-Instar  Drosophila Melanogaster

This protocol describes a method to record the descending electrical activity of the Drosophila melanogaster central nervous system to enable the cost-efficient and convenient testing of pharmacological agents, genetic mutations of neural proteins, and/or the role of unexplored physiological pathways.

Electrophysiological Recording of The Central Nervous System Activity of Third-Instar Drosophila Melanogaster

The majority of the currently available insecticides target the nervous system and genetic mutations of invertebrate neural proteins oftentimes yield ...

Research

JoVE Journal

Neuroscience

Visualization of the Embryonic Nervous System in Whole-mount Drosophila Embryos

Visualization of the Embryonic Nervous System in Whole-mount Drosophila Embryos

The Drosophila embryo is an attractive model system for investigating the cellular and molecular basis of neuronal development. Here we describe the ...

Multimodal Imaging of Stem Cell Implantation in the Central Nervous System of Mice

During the past decade, stem cell transplantation has gained increasing interest as primary or secondary therapeutic modality for a variety of diseases, ...

Production of Lentiviral Vectors for Transducing Cells from the Central Nervous System

Efficient gene delivery in the central nervous system (CNS) is important in studying gene functions, modeling neurological diseases and developing ...

Labeling of Single Cells in the Central Nervous System of Drosophila melanogaster

Labeling of Single Cells in the Central Nervous System of Drosophila melanogaster

In this  article we describe how to individually label neurons in the embryonic CNS of Drosophila melanogaster by juxtacellular injection of the ...

An Injury Paradigm to Investigate Central Nervous System Repair in Drosophila

An Injury Paradigm to Investigate Central Nervous System Repair in Drosophila

An experimental method has been developed to investigate the cellular responses to central nervous system (CNS) injury using the fruit-fly Drosophila. ...

Direct Intraventricular Delivery of Drugs to the Rodent Central Nervous System

Due to an inability to cross the blood brain barrier, certain drugs need to be directly delivered into the central nervous system (CNS). Our lab focuses ...

Electrophysiological Recording From Drosophila Labellar Taste Sensilla

Electrophysiological Recording From Drosophila Labellar Taste Sensilla

The peripheral taste response of insects can be powerfully investigated with electrophysiological techniques. The method described here allows the ...

Determination of the Spontaneous Locomotor Activity in Drosophila melanogaster

Determination of the Spontaneous Locomotor Activity in Drosophila melanogaster

Drosophila melanogaster has been used as an excellent model organism to study environmental and genetic manipulations that affect behavior. One such ...

In vivo Optogenetic Stimulation of the Rodent Central Nervous System

In vivo Optogenetic Stimulation of the Rodent Central Nervous System

The ability to probe defined neural circuits in awake, freely-moving animals with cell-type specificity, spatial precision, and high temporal resolution ...

Optical Clearing of the Mouse Central Nervous System Using Passive CLARITY

Traditionally, tissue visualization has required that the tissue of interest be serially sectioned and imaged, subjecting each tissue section to unique ...