|
|
||||||||
Journal of Neurophysiology, Vol 71, Issue 6 2503-2516, Copyright © 1994 by APS
ARTICLES |
P. Cardi and F. Nagy
Universite de Bordeaux I, Centre National de la Recherche Scientifique, Laboratoire de Neurobiologie et Physiologie Comparees, Arcachon, France.
1. Two modulatory neurons, P and commissural pyloric (CP), known to be involved in the long-term maintenance of pyloric central pattern generator operation in the rock lobster Homarus gammarus, are members of the commissural pyloric oscillator (CPO), a higher-order oscillator influencing the pyloric network. 2. The CP neuron was endogenously oscillating in approximately 30% of the preparations in which its cell body was impaled. Rhythmic inhibitory feedback from the pyloric pacemaker anterior burster (AB) neuron stabilized the CP neuron's endogenous rhythm. 3. The organization of the CPO is described. Follower commissural neurons, the F cells, and the CP neuron receive a common excitatory postsynaptic potential from another commissural neuron, the large exciter (LE). When in oscillatory state, CP in turn excites the LE neuron. This positive feedback may maintain long episodes of CP oscillations. 4. The pyloric pacemaker neurons follow the CPO rhythm with variable coordination modes (i.e., 1:1, 1:2) and switch among these modes when their membrane potential is modified. The CPO inputs strongly constrain the pyloric period, which as a result may adopt only a few discrete values. This effect is based on mechanisms of entrainment between the CPO and the pyloric oscillator. 5. Pyloric constrictor neurons show differential sensitivity from the pyloric pacemaker neurons with respect to the CPO inputs. Consequently, their bursting period can be a shorter harmonic of the bursting period of the pyloric pacemakers neurons. 6. The CPO neurons seem to be the first example of modulatory gating neurons that also give timing cues to a rhythmic pattern generating network.
This article has been cited by other articles:
![]() |
D. M. Blitz, R. S. White, S. R. Saideman, A. Cook, A. E. Christie, F. Nadim, and M. P. Nusbaum A newly identified extrinsic input triggers a distinct gastric mill rhythm via activation of modulatory projection neurons J. Exp. Biol., March 15, 2008; 211(6): 1000 - 1011. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. S. Richards, W. L. Miller, and E. Marder Maturation of Lobster Stomatogastric Ganglion Rhythmic Activity J Neurophysiol, October 1, 1999; 82(4): 2006 - 2009. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Faumont, J. Simmers, and P. Meyrand Activation of a Lobster Motor Rhythm-Generating Network by Disinhibition of Permissive Modulatory Inputs J Neurophysiol, November 1, 1998; 80(5): 2776 - 2780. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |