Abstract
Evoked synaptic potential were recorded extracellularly in experiments on a nervemuscle preparation of the frog sartorius muscle. A decrease in evoked transmitter release was found from the proximal to the distal parts of the nerve ending, due to a decrease in the probability of transmitter quantum release. The terminal portions of the synapse are less sensitive than the proximal parts to changes in Ca++ concentration, they show less marked facilitation of transmitter release during paired and repetitive stimulation, and exhibit deeper and more rapidly developing depression. It is concluded that differences in transmitter release in the terminal parts of the synapse are due to the low reserves of transmitter and the lower premeability of the presynaptic membrane to Ca++.
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S. V. Kurashov Kazan' State Medical Institute, Ministry of Health of the RSFSR. Translated from Neirofiziologiya, Vol. 15, No. 4, pp. 362–369, July–August, 1983.
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Zefirov, A.L. Transmitter release in proximal and distal parts of a nerve terminal of the frog sartorius muscle. Neurophysiology 15, 262–268 (1983). https://doi.org/10.1007/BF01059865
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DOI: https://doi.org/10.1007/BF01059865