Elsevier

Neuroscience Letters

Volume 76, Issue 3, 19 May 1987, Pages 301-306
Neuroscience Letters

Muscarine affects calcium-currents in rat hippocampal pyramidal cells in vitro

https://doi.org/10.1016/0304-3940(87)90419-8Get rights and content

Abstract

Ca2+-currents were recorded from single CA, pyramidal cells in hippocampal slice cultures, voltage-clamped through a single Cs4- or K+-filled microelectrode and perfused with Hanks' balanced salt solution containing 1 μM tetrodotoxin and 10 mM tetraethylammionium. The Ca2+-current was reversibly reduced by bath-perfused muscarine (10 100 μM). This effect was inhibited by pirenzepine (10 μM) or atropine (1 μM). In K+-filled cells, inhibition was preceded by a phase of inward current enhancement; this was considered to be secondary to rapid outward current inhibition induced by muscarine since it was reduced when outward currents were previously inhibited with Ba2+. In partially clamped or unclamped cells inhibition of Ca2+-current leads to a shortening of the Ca2+-spike plateau.

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