|
|
||||||||
Thomas Hunt Morgan School of Biological Sciences, University of Kentucky, Lexington, Kentucky 40506-0225
In the crayfish opener neuromuscular preparation, regional differences in synaptic transmission are observed among the terminals of a single motoneuron. With a single stimulus, the high-output terminals of the proximal region of the muscle produce a larger excitatory postsynaptic potential than do the low-output terminals of the central region of the muscle. We tested the hypothesis that the low-output terminals exhibit more facilitation than do high-output terminals for twin-pulse, train, and continuous-stimulation paradigms. Previous studies have not employed several stimulation paradigms to induce facilitation among high- and low-output terminals of a single motoneuron. We found that the high-output terminals on the proximal fibers facilitate more than the low-output terminals on the central muscle fibers, in contrast with previous studies on similar muscles. The difference in measured facilitation is dependent on the stimulation paradigm. These results are important because ultrastructural differences between these high- and low-output terminals are known and can be used for correlatation with physiological measurements. Short-term facilitation is a form of short-term memory at the synaptic level, and the processes understood at the crayfish neuromuscular junction may well be applicable to all chemical synapses.
crayfish; neuromuscular junction; synapse
This article has been cited by other articles:
![]() |
S. Logsdon, A. F. M. Johnstone, K. Viele, and R. L. Cooper Regulation of synaptic vesicles pools within motor nerve terminals during short-term facilitation and neuromodulation J Appl Physiol, February 1, 2006; 100(2): 662 - 671. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. M. Sparks and R. L. Cooper 5-HT offsets homeostasis of synaptic transmission during short-term facilitation J Appl Physiol, May 1, 2004; 96(5): 1681 - 1690. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. L. Mykles, S. Medler, A. Koenders, and R. Cooper Myofibrillar protein isoform expression is correlated with synaptic efficacy in slow fibres of the claw and leg opener muscles of crayfish and lobster J. Exp. Biol., February 15, 2002; 205(4): 513 - 522. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |