This research was supported by NIH grant NS047073 and NSF grant DMS1010434.

1. Preparation of Solutions
<ol>
	<li>To prepare magnesium chloride solution that is isotonic to the seawater in which the animals are kept (~ 1,000 millosmolar), mark a large jug at the level of the desired volume. Fill the jug with distilled water to approximately 80% of this level, and weigh out the appropriate amount of magnesium chloride hexahydrate to create a 333 mM solution in the final volume. Add the magnesium chloride to the jug, close the lid and shake vigorously until the magnesium chloride is fully dissol...

<ol>
	<li>Neustadter, D. M., Herman, R. L., Drushel, R. F., Chestek, D. W., Chiel, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+kinematics+of+multifunctionality:+comparisons+of+biting+and+swallowing+in+Aplysia+californica.">The kinematics of multifunctionality: comparisons of biting and swallowing in Aplysia californica.</a> J. Exp. Biol. 210, 238-260 (2007).</li><li>Morton, D. W., Chiel, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+buccal+nerve+activity+that+distinguishes+ingestion+from+rejection+can+be+used+to+predict+behavioral+transitions+in+Aplysia.">In vivo buccal nerve activity that distinguishes ingestion from rejection can be used to predict behavioral transitions in Aplysia.</a> J. Comp. Physiol. A. 172, 17-32 (1993).</li><li>Hurwitz, I., Neustadter, D., Morton, D. W., Chiel, H. J., Susswein, 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=Activity+patterns+of+the+B31/B32+pattern+initiators+innervating+the+I2+muscle+of+the+buccal+mass+during+normal+feeding+movements+in+Aplysia+californica.">Activity patterns of the B31/B32 pattern initiators innervating the I2 muscle of the buccal mass during normal feeding movements in Aplysia californica.</a> J. Neurophys. 75, 1309-1326 (1996).</li><li>Cullins, M. J., Chiel, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrode+fabrication+and+implantation+in+Aplysia+californica+for+multi-channel+neural+and+muscular+recordings+in+intact,+freely+behaving+animals.">Electrode fabrication and implantation in Aplysia californica for multi-channel neural and muscular recordings in intact, freely behaving animals.</a> J. Vis. Exp. (40), e1791 (2010).</li><li>Warman, E. N., Chiel, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+technique+for+chronic+single+extracellular+recording+in+freely+behaving+animals+using+pipette+electrodes.">A new technique for chronic single extracellular recording in freely behaving animals using pipette electrodes.</a> J. Neurosci. Methods. 57, 161-169 (1995).</li><li>Lu, H., Chestek, C. A., Shaw, K. M., Chiel, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+extracellular+stimulation+of+individual+neurons+in+ganglia.">Selective extracellular stimulation of individual neurons in ganglia.</a> J. Neural Eng. 5, 287-309 (2008).</li><li>Church, P. J., Lloyd, P. E. <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+diverse+neuropeptide+cotransmitters+by+identified+motor+neurons+in+Aplysia.">Expression of diverse neuropeptide cotransmitters by identified motor neurons in Aplysia.</a> J. Neurosci. 11, 618-625 (1991).</li><li>Church, P. J., Lloyd, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activity+of+multiple+identified+motor+neurons+recorded+intracellularly+during+evoked+feedinglike+motor+programs+in+Aplysia.">Activity of multiple identified motor neurons recorded intracellularly during evoked feedinglike motor programs in Aplysia.</a> J. Neurophys. 72, 1794-1809 (1994).</li><li>Nargeot, R. N., Baxter, D. A., Byrne, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contingent-dependent+enhancement+of+rhythmic+motor+patterns:+an+in+vitro+analog+of+operant+conditioning.">Contingent-dependent enhancement of rhythmic motor patterns: an in vitro analog of operant conditioning.</a> J. Neurosci. 17, 8093-8105 (1997).</li><li>Kandel, E. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Behavioral biology of Aplysia. , (1979).</li><li>Scott, M. L., Govind, C. K., Kirk, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuromuscular+organization+of+the+buccal+system+in+Aplysia+californica.">Neuromuscular organization of the buccal system in Aplysia californica.</a> J. Comp. Neurol. 312, 207-222 (1991).</li><li>Susswein, A. J., Rosen, S. C., Gapon, S., Kupfermann, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+buccal+motor+programs+elicited+by+a+cholinergic+agonist+applied+to+the+cerebral+ganglion+of+Aplysia+californica.">Characterization of buccal motor programs elicited by a cholinergic agonist applied to the cerebral ganglion of Aplysia californica.</a> J. Comp. Physiol. A. 179, 509-524 (1996).</li><li>Kupfermann, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Feeding+behavior+in+Aplysia:+A+simple+system+for+the+study+of+motivation.">Feeding behavior in Aplysia: A simple system for the study of motivation.</a> Behav. Biol. 10, 1-26 (1974).</li><li>Morton, D. W., Chiel, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+timing+of+activity+in+motor+neurons+that+produce+radula+movements+distinguishes+ingestion+from+rejection+in+Aplysia.">The timing of activity in motor neurons that produce radula movements distinguishes ingestion from rejection in Aplysia.</a> J. Comp. Physiol. A. 173, 519-536 (1993).</li><li>Weiss, K. R., Chiel, H. J., Koch, U., Kupfermann, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activity+of+an+identified+histaminergic+neuron,+and+its+possible+role+in+arousal+of+feeding+behavior+in+semi-intact+Aplysia.">Activity of an identified histaminergic neuron, and its possible role in arousal of feeding behavior in semi-intact Aplysia.</a> J. Neurosci. 6, 2403-2415 (1986).</li><li>Jing, J., Weiss, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+variants+of+a+motor+act+in+a+modular+and+hierarchical+motor+network.">Generation of variants of a motor act in a modular and hierarchical motor network.</a> Curr. Biol. 15, 1712-1721 (2005).</li><li>Jing, J., Weiss, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+mechanisms+of+motor+program+switching+in+Aplysia.">Neural mechanisms of motor program switching in Aplysia.</a> J. Neurosci. 21, 7349-7362 (2001).</li><li>Morgan, P. T., Jing, J., Vilim, F. S., Weiss, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interneuronal+and+peptidergic+control+of+motor+pattern+switching+in+Aplysia.">Interneuronal and peptidergic control of motor pattern switching in Aplysia.</a> J. Neurophysiol. 87, 49-61 (2002).</li><li>Jing, J., Cropper, E. C., Hurwitz, I., Weiss, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+construction+of+movement+with+behavior-specific+and+behavior-independent+modules.">The construction of movement with behavior-specific and behavior-independent modules.</a> J. Neurosci. 24, 6315-6325 (2004).</li></ol>

No conflicts of interest declared.

Previous work has characterized Aplysia motor programs in the intact animal and in reduced preparations, such as isolated ganglia. In the intact animal, although recordings of individual neurons have been obtained5, such experiments are very difficult, and electrodes cannot be moved from neuron to neuron during feeding. In isolated ganglia, the feeding movements induced by neural activity cannot be observed. The suspended buccal mass preparation bridges the gap between these two extremes.
<p...

<table border="1">
	<tbody>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Sodium chloride</td>
			<td>Fisher Scientific</td>
			<td>S671</td>
			<td>Biological, Certified</td>
		</tr>
		<tr>
			<td>Potassium chloride</td>
			<td>Fisher Scientific</td>
			<td>P217</td>
			<td>Certified ACS</td>
		</tr>
		<tr>
			<td>Magnesium chloride hexahydrate</td>
			<td>Acros Organics</td>
			<td>19753</td>
			<td>99%</td>
		</tr>
		<tr>
			<td>Magnesium sulfate heptahydrate</td>
			<td>Fisher Scientific</td>
			<td>M63</td>
			<td>Certified ACS</td>
		</tr>
		<tr>
			<td>Calcium chloride dihydrate</td>
			<td>Fisher Scientifc</td>
			<td>C79</td>
			<td>Certified ACS</td>
		</tr>
		<tr>
			<td>Glucose (dextrose)</td>
			<td>Sigma-Aldrich</td>
			<td>G7528</td>
			<td>BioXtra</td>
		</tr>
		<tr>
			<td>MOPS buffer</td>
			<td>Acros Organics</td>
			<td>17263</td>
			<td>99%</td>
		</tr>
		<tr>
			<td>Carbachol</td>
			<td>Acros Organics</td>
			<td>10824</td>
			<td>99%</td>
		</tr>
		<tr>
			<td>Sodium hydroxide</td>
			<td>Fisher Scientific</td>
			<td>SS255</td>
			<td>Certified</td>
		</tr>
		<tr>
			<td>Hydrochloric acid</td>
			<td>Fisher Scientific</td>
			<td>SA49</td>
			<td>Certified</td>
		</tr>
		<tr>
			<td>Single-barreled capillary glass</td>
			<td>A-M Systems</td>
			<td>6150</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Flaming-Brown micropipette puller model P-80/PC</td>
			<td>Sutter Instruments</td>
			<td>&nbsp;</td>
			<td>Filament used: FT345B</td>
		</tr>
		<tr>
			<td>Enamel coated stainless steel wire</td>
			<td>California Fine Wire</td>
			<td>&nbsp;</td>
			<td>0.001D, coating h</td>
		</tr>
		<tr>
			<td>Household Silicone II Glue</td>
			<td>GE</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Duro Quick-Gel superglue</td>
			<td>Henkel corp.</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>A-M Systems model 1700 amplifier</td>
			<td>A-M Systems</td>
			<td>&nbsp;</td>
			<td>Filter settings: 300-500 Hz nerves,10-500 Hz I2 muscle</td>
		</tr>
		<tr>
			<td>Pulsemaster Multi-Channel Stimulator</td>
			<td>World Precision Instruments</td>
			<td>A300</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Stimulus Isolator</td>
			<td>World Precision Instruments</td>
			<td>A360</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>AxoGraph X</td>
			<td>AxoGraph Scientific</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Veeder-Root Totalizing Counter</td>
			<td>Danaher</td>
			<td>C342-0562</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Gold Connector Pins</td>
			<td>Bulgin</td>
			<td>SA3148/1</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Gold Connector Sockets</td>
			<td>Bulgin</td>
			<td>SA3149/1</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Sylgard 184 Silicone Elastomer</td>
			<td>Dow Corning</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>100 x 50 mm Crystalizing Dish</td>
			<td>Pyrex</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>High Vacuum Grease</td>
			<td>Dow Corning</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Pipet Tips</td>
			<td>Fisher Scientific</td>
			<td>21-375D</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Minutien Pins</td>
			<td>Fine Science Tools</td>
			<td>26002-10</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Modeling Clay</td>
			<td>Sargent Art</td>
			<td>22-4400</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Silk Sutures</td>
			<td>Ethicon</td>
			<td>K89OH</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Whisper Air Pump</td>
			<td>Tetra</td>
			<td>77849</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Aquarium Tubing</td>
			<td>Eheim</td>
			<td>7783</td>
			<td>12/16 mm</td>
		</tr>
		<tr>
			<td>Elite Airstone</td>
			<td>Hagen</td>
			<td>A962</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Vannas Spring Scissors</td>
			<td>Fine Science Tools</td>
			<td>15000-08</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Dumont #5 Fine Forceps</td>
			<td>Fine Science Tools</td>
			<td>11254-20</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Yaki Sushi Nori Seaweed</td>
			<td>Rhee Bros</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Kimwipes</td>
			<td>Kimberly-Clark</td>
			<td>34155</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

an in vitro preparation for eliciting and recording feeding motor programs with physiological movements in aplysia californica

Multifunctionality, the ability of one peripheral structure to generate multiple, distinct behaviors1, allows animals to rapidly adapt their behaviors to changing environments. The marine mollusk Aplysia californica provides a tractable system for the study of multifunctionality. During feeding, Aplysia generates several distinct types of behaviors using the same feeding apparatus, the buccal mass. The ganglia that control these behaviors contain a number of large, identified neurons that are accessible to electrophysiological study. The activity of these neurons has been described in motor programs that can be divided into two types, ingestive and egestive programs, based on the timing of neural activity that closes the food grasper relative to the neural activity that protracts or retracts the grasper2. However, in isolated ganglia, the muscle movements that would produce these behaviors are absent, making it harder to be certain whether the motor programs observed are correlates of real behaviors. In vivo, nerve and muscle recordings have been obtained corresponding to feeding programs2,3,4, but it is very difficult to directly record from individual neurons5. Additionally, in vivo, ingestive programs can be further divided into bites and swallows1,2, a distinction that is difficult to make in most previously described in vitro preparations.
The suspended buccal mass preparation (Figure 1) bridges the gap between isolated ganglia and intact animals. In this preparation, ingestive behaviors - including both biting and swallowing - and egestive behaviors (rejection) can be elicited, at the same time as individual neurons can be recorded from and stimulated using extracellular electrodes6. The feeding movements associated with these different behaviors can be recorded, quantified, and related directly to the motor programs. The motor programs in the suspended buccal mass preparation appear to be more similar to those observed in vivo than are motor programs elicited in isolated ganglia. Thus, the motor programs in this preparation can be more directly related to in vivo behavior; at the same time, individual neurons are more accessible to recording and stimulation than in intact animals. Additionally, as an intermediate step between isolated ganglia and intact animals, findings from the suspended buccal mass can aid in interpretation of data obtained in both more reduced and more intact settings. The suspended buccal mass preparation is a useful tool for characterizing the neural control of multifunctionality in Aplysia.

When an extracellular electrode is positioned above a neuron's soma and used to stimulate the neuron, a one-for-one correspondence between spikes on the soma channel and on the nerve(s) the neuron projects to can be observed (Figure 6, left panel, stimulation of identified neuron B9). The soma channel (top channel) is set to stimulating mode when the current is applied (time 1 in the figure), and is then quickly switched to recording mode (time 2). By maintaining the position of the electrode, the...

Watch this Scientific Journal Video about An In Vitro Preparation for Eliciting and Recording Feeding Motor Programs with Physiological Movements in Aplysia californica at JoVE.com

An In Vitro Preparation for Eliciting and Recording Feeding Motor Programs with Physiological Movements in Aplysia californica

We describe a technique to extracellularly record and stimulate from nerves, muscles, and individual identified neurons in vitro while eliciting and observing different types of feeding behaviors in the feeding apparatus of Aplysia.

An In Vitro Preparation for Eliciting and Recording Feeding Motor Programs with Physiological Movements in Aplysia californica

Multifunctionality, the ability of one peripheral  structure to generate multiple, distinct behaviors1, allows animals  to rapidly adapt their behaviors ...

an-vitro-preparation-for-eliciting-recording-feeding-motor-programs

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Neuroscience

10.5K Views.  Case Western Reserve University. We describe a technique to extracellularly record and stimulate from nerves, muscles, and individual identified neurons in vitro while eliciting and observing different types of feeding behaviors in the feeding apparatus of Aplysia.