Skip to main content
PMC home page
The Journal of Physiology logoLink to The Journal of Physiology
. 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.

Full text

PDF
629

Selected References

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

  1. BLACKMAN J. G., GINSBORG B. L., RAY C. On the quantal release of the transmitter at a sympathetic synapse. J Physiol. 1963 Jul;167:402–415. doi: 10.1113/jphysiol.1963.sp007158. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. DEL CASTILLO J., KATZ B. Changes in end-plate activity produced by presynaptic polarization. J Physiol. 1954 Jun 28;124(3):586–604. doi: 10.1113/jphysiol.1954.sp005131. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. DEL CASTILLO J., KATZ B. Statistical factors involved in neuromuscular facilitation and depression. J Physiol. 1954 Jun 28;124(3):574–585. doi: 10.1113/jphysiol.1954.sp005130. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. KATZ B., MILEDI R. PROPAGATION OF ELECTRIC ACTIVITY IN MOTOR NERVE TERMINALS. Proc R Soc Lond B Biol Sci. 1965 Feb 16;161:453–482. doi: 10.1098/rspb.1965.0015. [DOI] [PubMed] [Google Scholar]
  5. Katz B., Miledi R. A study of synaptic transmission in the absence of nerve impulses. J Physiol. 1967 Sep;192(2):407–436. doi: 10.1113/jphysiol.1967.sp008307. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Katz B., Miledi R. Tetrodotoxin and neuromuscular transmission. Proc R Soc Lond B Biol Sci. 1967 Jan 31;167(1006):8–22. doi: 10.1098/rspb.1967.0010. [DOI] [PubMed] [Google Scholar]
  7. Katz B., Miledi R. The effect of local blockage of motor nerve terminals. J Physiol. 1968 Dec;199(3):729–741. doi: 10.1113/jphysiol.1968.sp008675. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. LILEY A. W., NORTH K. A. An electrical investigation of effects of repetitive stimulation on mammalian neuromuscular junction. J Neurophysiol. 1953 Sep;16(5):509–527. doi: 10.1152/jn.1953.16.5.509. [DOI] [PubMed] [Google Scholar]
  9. LUNDBERG A., QUILISCH H. Presynaptic potentiation and depression of neuromuscular transmission in frog and rat. Acta Physiol Scand Suppl. 1953;111:111–120. [PubMed] [Google Scholar]
  10. MARTIN A. R. A further study of the statistical composition on the end-plate potential. J Physiol. 1955 Oct 28;130(1):114–122. doi: 10.1113/jphysiol.1955.sp005397. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Mallart A., Martin A. R. An analysis of facilitation of transmitter release at the neuromuscular junction of the frog. J Physiol. 1967 Dec;193(3):679–694. doi: 10.1113/jphysiol.1967.sp008388. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. OTSUKA M., ENDO M., NONOMURA Y. Presynaptic nature of neuromuscular depression. Jpn J Physiol. 1962 Dec 15;12:573–584. doi: 10.2170/jjphysiol.12.573. [DOI] [PubMed] [Google Scholar]
  13. Rahamimoff R. A dual effect of calcium ions on neuromuscular facilitation. J Physiol. 1968 Mar;195(2):471–480. doi: 10.1113/jphysiol.1968.sp008468. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. TAKEUCHI A., TAKEUCHI N. Electrical changes in pre- and postsynaptic axons of the giant synapse of Loligo. J Gen Physiol. 1962 Jul;45:1181–1193. doi: 10.1085/jgp.45.6.1181. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. TAKEUCHI A., TAKEUCHI N. Further analysis of relationship between end-plate potential and end-plate current. J Neurophysiol. 1960 Jul;23:397–402. doi: 10.1152/jn.1960.23.4.397. [DOI] [PubMed] [Google Scholar]
  16. TAKEUCHI A., TAKEUCHI N. On the permeability of end-plate membrane during the action of transmitter. J Physiol. 1960 Nov;154:52–67. doi: 10.1113/jphysiol.1960.sp006564. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. TAKEUCHI A. The long-lasting depression in neuromuscular transmission of frog. Jpn J Physiol. 1958 Jun 15;8(2):102–113. doi: 10.2170/jjphysiol.8.102. [DOI] [PubMed] [Google Scholar]
  18. THIES R. E. NEUROMUSCULAR DEPRESSION AND THE APPARENT DEPLETION OF TRANSMITTER IN MAMMALIAN MUSCLE. J Neurophysiol. 1965 May;28:428–442. doi: 10.1152/jn.1965.28.3.427. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES