Abstract
SEVERAL lines of evidence indicate that an influx of Ca2+ ions accompanies transmitter activation of the postsynaptic membrane at the neuromuscular junction1–5. We report here that we have now investigated the elementary characteristics of the Ca2+ current by bathing muscles in CaCl2 solutions containing no Na+ ions, so that Ca2+ is the only ion available to carry any appreciable inward current1,3,6,7. The single channel current (i) and mean lifetime (τ) of the postsynaptic channels were then determined by the technique of noise analysis8,9. It was found that τ in the Ca2+ solution was shorter than in normal Ringer, but that the voltage dependence of τ was unchanged. The elementary current showed a non-linear voltage dependence, unlike the linear dependence in normal solution8.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Takeuchi, N. J. Physiol., Lond. 167, 141–155 (1963).
Jenkinson, D. H. & Nicholls, J. G. J. Physiol., Lond. 159, 111–127 (1961).
Katz, B. & Miledi, R. J. Physiol., Lond. 203, 459–487 (1969).
Evans, R. H. J. Physiol., Lond. 240, 517–533 (1974).
Miledi, R., Parker, I. & Schalow, G. J. Physiol., Lond. 269, 11–13P (1977).
Heuser, J., Katz, B. & Miledi, R. Proc. R. Soc. B178, 407–415 (1971).
Takeuchi, N. J. Physiol., Lond. 167, 128–140 (1963).
Anderson, C. R. & Stevens, C. F. J. Physiol., Lond. 235, 655–691 (1973).
Katz, B. & Miledi, R. J. Physiol., Lond. 224, 665–699 (1972).
Katz, B. & Miledi, R. J. Physiol., Lond. 203, 459–487 (1969).
Sanchez, J. A. & Stefani, E. J. Physiol., Lond. 283, 197–209 (1978).
Hagiwara, S. & Nakajima, S. J. gen. Physiol. 49, 793–806 (1966).
Baker, P. F., Meves, H. & Ridgeway, E. B. J. Physiol., Lond. 231, 511–526 (1973).
Cohen, I. & Van der Kloot, W. Nature 271, 77–79 (1978).
Goldman, D. E. J. gen. Physiol. 27, 37–60 (1943).
Hodgkin, A. L. & Katz, B. J. Physiol., Lond. 108, 37–77 (1949).
Meves, H. Pflügers Arch. ges. Physiol. 304, 215–241 (1968).
Lewis, C. A. J. Physiol., Lond. 286, 417–445 (1979).
Van Helden, D., Hammill, O. P. & Gage, P. W. Nature 269, 711–713 (1977).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
BREGESTOVSKI, P., MILEDI, R. & PARKER, I. Calcium conductance of acetylcholine-induced endplate channels. Nature 279, 638–639 (1979). https://doi.org/10.1038/279638a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/279638a0
This article is cited by
-
Acetylcholine reduces the slow calcium current in embryonic skeletal muscle cells in culture
Pfl�gers Archiv European Journal of Physiology (1993)
-
Cholinergic responses in cloned human TE671/RD tumour cells
Pfl�gers Archiv European Journal of Physiology (1993)
-
Transient elevation of spontaneous release at the frog neuromuscular junction following acetylcholine iontophoresis
Pflügers Archiv (1988)
-
Permeability to Ca2+ of the acetylcholine receptor channel of denervated mouse muscles in the presence of Na+ and of some other cations
Pflügers Archiv - European Journal of Physiology (1988)
-
Modulation by Ca ions of short-term plasticity of the cholinoreceptive membrane in molluscan neurons
Neuroscience and Behavioral Physiology (1987)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.
