Elsevier

Neuroscience Letters

Volume 155, Issue 2, 11 June 1993, Pages 199-203
Neuroscience Letters

Cl channels are randomly activated by continuous GABA secretion in cultured embryonic rat hippocampal neurons

https://doi.org/10.1016/0304-3940(93)90707-RGet rights and content

Abstract

Throughout the adult vertebrate central nervous system (CNS) γ-aminobutyric acid (GABA) mediates transient Cl conductances commonly identified as fast, Cl-dependent inhibitory synaptic signals [Prog. Neurobiol., 36 (1991) 35–92). In the rat hippocampus Cl-dependent excitatory transients mediated by GABA emerge during the first postnatal week superimposed on a steady-state baseline that is also Cl- and GABA-dependent [Int. J. Dev. Neurosci., 8 (1990) 481–490]. Here we report that many embryonic rat hippocampal neurons cultured for hours to days exhibit random fluctuations in Cl channel activity that are mediated by continuous secretion of GABA in the absence of transients. Thus, GABA is broadcast tonically before it is released transiently.

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Present Address: Albert Einstein College of Medicine, Department of Neuroscience, Yeshiva University, Bronx, N.Y. 10461, USA.

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