Chapter 9 Cl− -channels

Abstract

Publisher Summary This chapter provides an overview on the properties of the different types of Cl - -channels in various mammalian cells and provides a review of C1 - channels on a molecular basis. Cl - -channels can be subdivided into three categories: (1) large channels (> 100 pS), (2) intermediate channels (20–100pS), and (3) small channels ( - -channels of the central nervous system (CNS) are gated by the respective agonists, gamma-aminobutyric acid (GABA) and glycine. Most C1 - -channels can be inhibited by disulphonate stilbenes. Muscle Cl - -channels can be inhibited by anthracene-9-carboxylate (A9C) and probably by indanyloxy acetic acid 94 (IAA-94). The intermediate-conductance outwardly rectifying (ICOR) Cl - -channel is fairly sensitive to 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB). None of these probes, except for the GABA- and glycine-receptor Cl - -channels, is of sufficient affinity and selectivity to permit the channel identification by its use. This dilemma is one of the reasons why the purification of epithelial Cl - -channels lags behind that of the CNS Cl - -channels.