Journal of Neurophysiology, Vol 73, Issue 1 39-55, Copyright © 1995 by APS

ARTICLES

Functional neural regeneration in the feeding system of Aplysia: behavioral recovery correlated with changes in buccal motor output

M. L. Scott, Y. Li and M. D. Kirk
Division of Biological Sciences, University of Missouri-Columbia 65211.

1. We tested for functional neural regeneration in the feeding system of Aplysia after bilateral transections or crushes of the cerebral-buccal connectives (CBCs) with the use of behavioral analyses and electrophysiological recordings. 2. Both types of lesion selectively abolished rhythmic consummatory behavior, dramatically increasing bite latency and interbite interval, and decreasing bite magnitude. Appetitive feeding behavior was not affected. 3. About 2 wk after CBC crush, bite latency, bite magnitude, and interbite interval began to recover, as rhythmic biting reappeared; complete recovery of rhythmic biting occurred within 60 days. Rhythmic biting never recovered after transection of the CBCs. 4. The recovery of rhythmic biting was correlated with changes in buccal motor output, which were assessed with the use of in vivo recordings from buccal nerve 4 in freely moving Aplysia. Initially, some bursting in nerve 4 occurred without overt bites; with full recovery of biting, a 1:1 correspondence between bursts in nerve 4 and overt bites returned. 5. CBC lesions caused a functional separation between biting and swallowing; at early times postlesion, subjects displayed apparently normal rhythmic swallowing even though rhythmic biting had been eliminated. However, there was a disruption of the 1:1 correspondence between nerve 4 bursts and swallows, which persisted until consummatory feeding fully recovered. 6. Transection of the CBCs in animals that had fully recovered from a previous CBC crush again abolished rhythmic biting, suggesting that the recovery of consummatory feeding behavior was due to functional neural regeneration of cerebral-buccal connections.

This article has been cited by other articles:

				J. A. D. Sanchez, Y. Li, and M. D. Kirk Regeneration of Cerebral-Buccal Interneurons and Recovery of Ingestion Buccal Motor Programs in Aplysia After CNS Lesions J Neurophysiol, December 1, 2000; 84(6): 2961 - 2974. [Abstract] [Full Text] [PDF]

				H. A. Lechner, D. A. Baxter, and J. H. Byrne Classical Conditioning of Feeding in Aplysia: II. Neurophysiological Correlates J. Neurosci., May 1, 2000; 20(9): 3377 - 3386. [Abstract] [Full Text] [PDF]

				E. A. Kabotyanski, D. A. Baxter, S. J. Cushman, and J. H. Byrne Modulation of Fictive Feeding by Dopamine and Serotonin in Aplysia J Neurophysiol, January 1, 2000; 83(1): 374 - 392. [Abstract] [Full Text] [PDF]

				B. K. Modney, C. L. Sahley, and K. J. Muller Regeneration of a Central Synapse Restores Nonassociative Learning J. Neurosci., August 15, 1997; 17(16): 6478 - 6482. [Abstract] [Full Text] [PDF]

				J. A. D. Sanchez and M. D. Kirk Short-Term Synaptic Enhancement Modulates Ingestion Motor Programs of Aplysia J. Neurosci., July 15, 2000; 20(14): RC85 - RC85. [Abstract] [Full Text] [PDF]