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. 1970 Mar;206(3):629–644. doi: 10.1113/jphysiol.1970.sp009034

Depression of transmitter release at the neuromuscular junction of the frog

W J Betz
PMCID: PMC1348669  PMID: 5498509

Abstract

1. Depression of transmitter release produced by preceding conditioning stimulation was studied at the frog's neuromuscular junction.

2. Depression occurred when transmitter release was restricted to a short length of nerve terminal, or when release was initiated by electrotonic depolarization of the terminals after action potentials were abolished by tetrodotoxin.

3. Quantitative studies revealed a non-linear relationship between the estimated magnitude of `zero-time' depression and the amount of transmitter released by conditioning stimulation.

4. Two stimuli separated by 20-200 msec were given and the ratio of the end-plate potential amplitudes (V2/V1) was measured. This amplitude ratio increased during depression produced by stimuli preceding the test pair.

5. These observations may be explained by assuming that depression is associated with a reduction in release probability as well as a depletion of transmitter available for release.

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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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