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. 1973 Jan;228(1):241–257. doi: 10.1113/jphysiol.1973.sp010084

Delayed release of transmitter at the frog neuromuscular junction

R Rahamimoff, Y Yaari
PMCID: PMC1331238  PMID: 4346703

Abstract

1. After the end-plate potential (e.p.p.) there is an increase in the frequency of the miniature e.p.p.s. This delayed release of transmitter was studied at the frog neuromuscular junction, using conventional intracellular and extracellular recording techniques. E.p.p. amplitude was kept subthreshold by subnormal concentrations of activating divalent ions.

2. The ratio delayed release: initial release had values between 2 and 140%, depending on the experimental conditions; it decreased with an increase in Ca concentration and quantal content.

3. Delayed release is larger at low temperature than at room temperature.

4. Delayed release is statistically independent of the amplitude of the preceding e.p.p.

5. The time course of the decay of the delayed release is monotonic when strontium is the activating divalent ion; it shows a `dip' in more than 50% of the cases when Ca activated release.

6. The results were discussed in terms of the residual Ca ion hypothesis.

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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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