Format

Send to

Choose Destination
Neuron. 1992 May;8(5):937-45.

Potentiation of nicotinic receptor response by external calcium in rat central neurons.

Author information

1
UA CNRS D1284, Département des Biotechnologies, Institut Pasteur, Paris, France.

Abstract

Nicotinic acetylcholine receptor (nAChR) responses of rat medial habenular neurons are potentiated up to 3.5-fold by increasing the concentration of external Ca2+ in the millimolar range. This effect, independent of voltage, is probably due to the binding of Ca2+ to an external site. External Ca2+ decreases nAChR single-channel conductance at negative but not positive potentials, and it markedly enhances the frequency of opening of acetylcholine activated channels. The potentiating effect of Ca2+ is mimicked by Ba2+ and Sr2+, but barely by Mg2+. These data support the existence of positively acting allosteric sites for Ca2+, distinct from those involved in the decrease of single-channel conductance. A model in which external Ca2+ changes the properties of activation of the nAChR appears consistent with these data.

PMID:
1586487
DOI:
10.1016/0896-6273(92)90208-u
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center