Abstract
Some electrical properties of the synapses between central giant axons (presynaptic) and the motor giant axon (postsynaptic) of the crayfish abdominal nerve cord have been investigated. Postsynaptic potential change in response to presynaptic volleys contains two components: a spike potential and a synaptic potential of very long time course. Amplitude of the synaptic potential is graded according to the number of active presynaptic axons. Conductance increase in the synaptic membrane endures over most of the period of potential change, and it is this rather than the "electrical time constant" of the membrane that in large measure determines the form of the synaptic potential. Temporal summation of synaptic potential occurs during repetitive presynaptic stimulation, and after such stimulation the rate of decay of synaptic potential is greatly slowed.
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Selected References
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- COOMBS J. S., ECCLES J. C., FATT P. Excitatory synaptic action in motoneurones. J Physiol. 1955 Nov 28;130(2):374–395. doi: 10.1113/jphysiol.1955.sp005413. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FATT P. Biophysics of junctional transmission. Physiol Rev. 1954 Oct;34(4):674–710. doi: 10.1152/physrev.1954.34.4.674. [DOI] [PubMed] [Google Scholar]
- FATT P., KATZ B. An analysis of the end-plate potential recorded with an intracellular electrode. J Physiol. 1951 Nov 28;115(3):320–370. doi: 10.1113/jphysiol.1951.sp004675. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FRANK K., FUORTES M. G. Stimulation of spinal motoneurones with intracellular electrodes. J Physiol. 1956 Nov 28;134(2):451–470. doi: 10.1113/jphysiol.1956.sp005657. [DOI] [PMC free article] [PubMed] [Google Scholar]