Format

Send to

Choose Destination
Neuropharmacology. 1995 Nov;34(11):1443-51.

The concept of calcium concentration microdomains in synaptic transmission.

Author information

1
Department of Physiology and Neuroscience, New York University Medical Center, NY 10016, USA.

Abstract

Ever since the initial measurements of presynaptic calcium currents it has been evident that calcium triggers transmitter release quite rapidly. Several models indicate, as did the initial voltage clamp measurements, that the calcium concentration triggering such release could be very high at the entry site and that this concentration should be very short lasting. In order to determine this time course, calcium entry was studied at the squid giant synapse by imaging light emission from n-aequorin-J, intracellularly injected into the presynaptic terminal. The imaging utilized a video system capable of acquiring 4000 frames per sec. The results indicate that the calcium entry, triggered by action potentials, reaches a peak within 200 musec and has an overall duration of close to 800 musec, closely matching the duration of the presynaptic calcium current determined by voltage clamp results under similar conditions.

PMID:
8606792
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center