Abstract
Experiments on rats showed that carbachol (10 µM) appreciably quickens miniature end-plate potentials in the soleus muscle kept in medium with potassium chloride concentration increased to 13 mM. Potentiation of spontaneous mediator release also took place when the membrane potential of the muscle fibers was clamped at the level of the potassium equilibrium potential. It is concluded that the presynaptic action of carbachol on synaptic liberation of acetylcholine from motor nerve endings is unconnected with depolarization of the postsynaptic membrane but takes place as a result of the direct effect of the mimetic on motor nerve endings.
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Additional information
S. V. Kurashov Medical Institute, Ministry of Health of the RSFSR, Kazan'. Translated from Neirofiziologiya, Vol. 14, No. 2, pp. 185–189, March–April, 1982.
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Nikol'skii, E.E. Effect of carbachol on miniature end-plate potentials and currents of rat skeletal muscle. Neurophysiology 14, 148–152 (1982). https://doi.org/10.1007/BF01060186
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DOI: https://doi.org/10.1007/BF01060186