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. 1978 Mar;276:343–352. doi: 10.1113/jphysiol.1978.sp012238

The effects of pH and curare on the time course of end-plate currents at the neuromuscular junction of the frog.

A Mallart, J Molgó
PMCID: PMC1282429  PMID: 25959

Abstract

1. The effect of pH changes on synaptic currents has been analysed by external recording of the miniature end-plate currents (m.e.p.c.s) or by recording in voltage-clamped end-plates the current elicited by nerve stimulation (e.p.c.). 2. Changes in pH do not appreciably effect the peak amplitude of the current produced by a single quantum or by short ionophoretic pulses of acetylcholine. 3. The time constant of decay of the m.e.p.c.s is prolonged by about 50% in acid pH and shortened by about the same amount in alkaline pH. This effect is independent of the cholinesterase activity of the end-plate. 4. In curarized preparations the decay of the e.p.c. is shorter than in Mg-blocked end-plate even in the absence of cholinesterase blocking agents. 5. The action of pH on the decays can be explained by a titration of the surface charges of the membrane which effects the voltage dependent reaction that controls the rate of closing of the synaptic channels.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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