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GABA-Activated Bicarbonate Conductance

Influence on EGABA and on Postsynaptic pH Regulation

  • Chapter
Chloride Channels and Carriers in Nerve, Muscle, and Glial Cells

Abstract

γ-Aminobutyric acid (GABA) is a transmitter compound with a wide distribution and an exclusively inhibitory role in both vertebrate and invertebrate nervous systems (Gerschenfeld, 1973; Krnjević, 1974). Apart from its action on vertebrate GABAB-type receptors (see Dutar and Nicoll, 1988), the inhibitory effect of GABA is based on the opening of postsynaptic Cl − channels (Boistel and Fatt, 1958; Siggins and Gruol, 1986). An increase in postsynaptic Cl − conductance is also characteristic of glycine-mediated inhibition in vertebrates (Siggins and Gruol, 1986) and of acetylcholine-mediated inhibition in some invertebrate synapses (e.g., Kerkut and Thomas, 1964). The inhibitory effect of an increase in postsynaptic Cl − conductance is due to the fact that in most excitable cells, the equilibrium potential of chloride is at a level more negative than the threshold for action-potential generation.

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Authors and Affiliations

  1. Department of Zoology, Division of Physiology, University of Helsinki, SF-00100, Helsinki, Finland

    K. Kaila & J. Voipio

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  1. K. Kaila
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Editors and Affiliations

  1. Departamento de Farmacología y Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, 07000, Mexico, D.F., USA

    Francisco J. Alvarez-Leefmans

  2. Departamento de Neurobiología, Instituto Mexicano de Psiquiatría, 14370, Mexico, D.F., USA

    Francisco J. Alvarez-Leefmans

  3. Department of Physiology and Biophysics, University of Texas Medical Branch, 77550, Galveston, Texas, USA

    John M. Russell

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Kaila, K., Voipio, J. (1990). GABA-Activated Bicarbonate Conductance. In: Alvarez-Leefmans, F.J., Russell, J.M. (eds) Chloride Channels and Carriers in Nerve, Muscle, and Glial Cells. Springer, Boston, MA. https://doi.org/10.1007/978-1-4757-9685-8_12

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