Food-induced firing patterns in motoneurons innervating the pharynx ofAplysia kurodai
- 32 Downloads
InAplysia kurodai buccal ganglia, a pair of motoneurons (pharynx bursting or PB neurons), innervating the ipsilateral posterior pharynx muscles (Px) were identified by recording excitatory junction potentials (EJP) in the muscle fiber.
Seaweed extract applied to the lips in semi-intact preparations, induced rhythmic bursts of spikes in the PB neuron, out of phase with retractor muscle activity (response-I). Rhythmic bursts in the PB neuron were maintained even after cessation of retractor muscle activity (response-II). In both cases pharynx movements followed the bursts in the PB neuron.
During response-II, rhythmic changes of internal pressure in the pharynx followed the bursting activities of the PB neuron inducing sequential movements of the pharynx and esophagus.
The rhythmic change of membrane potential in the PB neuron and rhythmic pharynx movements during response-II were completely abolished by steady hyperpolarization of the PB neuron. In addition, rhythmic bursts of spikes were produced in the PB neuron by steady depolarization. Membrane properties of the PB neuron, in isolated preparations, were consistent with other endogenous bursting neurons, suggesting that rhythmic activity during response-II is an intrinsic property of the neuron.
Ipsilaterally, synchronous burst activities in the anterior and posterior Px were recorded during response-II. Rhythmic bursts generated in the PB neuron by steady depolarization, were synchronized with muscle potentials recorded in the ipsilateral anterior Px, suggesting that the PB neuron also induces the movement of the ipsilateral anterior Px.
KeywordsInternal Pressure Firing Pattern Rhythmic Activity Sequential Movement Burst Activity
- Ant. tentacle
- Buccal g.
- Cerebral g.
excitatory junction potential
excitatory post-synaptic potential
buccal nerve 1–3
- PB neuron
pharynx bursting neuron
- Post. tentacle
Unable to display preview. Download preview PDF.
- Arvanitaki A, Chalazonitis (1967) Electrical properties and temporal organization in oscillatory neurons. In: Salánki J (ed) Neurobiology of invertebrates. Akademiai Kiado, Budapest, pp 169–199Google Scholar
- Audesirk TE, Audesirk GJ (1979) Oral mechanoreceptors inTritonia diomedea: II. Role of feeding. J Comp Physiol 130:79–86Google Scholar
- Benjamin PR (1983) Gastropod feeding: behavioral and neural analysis of a complex multicomponent system. In: Roberts A, Roberts BL (eds) Neural origin of rhythmic movements (Symposia of the society for experimental biology). Cambridge University Press, Cambridge, pp 159–193Google Scholar
- Benson JA (1980) Burst reset and frequency control of the neuronal oscillators in the cardiac ganglion of the crab,Portunus sanguinolentus. J Exp Biol 87:285–313Google Scholar
- Frazier WT, Kandel ER, Kupfermann I, Waziri R, Coggeshall RE (1967) Morphological and functional properties of identified neurons in the abdominal ganglion ofAplysia californica. J Neurophysiol 30:1288–1351Google Scholar
- Howells HH (1942) The structure and function of the alimentary canal ofAplysia punctata. Q J Microsc Sci 83:357–397Google Scholar
- Kandel ER (1976) Cellular basis of behavior. Freeman, San FranciscoGoogle Scholar
- Kandel ER (1979) Behavioral biology ofAplysia. Freeman, San FranciscoGoogle Scholar
- Koch UT, Koester J, Weiss KR (1984) Neural mediation of cardiovascular effects of food arousal inAplysia. J Neurophysiol 51:126–135Google Scholar
- Kupfermann I (1974) Feeding behavior inAplysia: A simple system for the study of motivation. Behav Biol 10:1–26Google Scholar
- McClellan AD (1982) Movements and motor patterns of the buccal mass ofPleurobranchaea during feeding, regurgitation and rejection. J Exp Biol 98:195–211Google Scholar
- Peters M, Altrup U (1984) Motor organization in pharynx ofHelix pomatia. J Neurophysiol 52:389–409Google Scholar
- Pinsker HM, Kandel ER (1977) Short-term modulation of endogenous bursting rhythms by monosynaptic inhibition inAplysia neurons: Effects of contingent stimulation. Brain Res 125:51–64Google Scholar
- Rosen SC, Weiss KR, Kupfermann I (1982) Cross-modality sensory integration in the control of feeding inAplysia. Behav Neu Biol 35:56–63Google Scholar
- Selverston AI, Russel DF, Miller JP, King DG (1976) The stomatogastric nervous system: structure and function of a small neural network. Prog Neurobiol 7:215–290Google Scholar