Effect of extracellular chloride concentration on deactivation kinetics of rat ClC-1 chloride channel / 生理学报

ABSTRACT

The gating mechanism of ClC-1 chloride channel was studied in this paper by heteroexpression of rat wild type ClC-1 gene in Xenopus oocytes and by two-electrode voltage clamping technique. The deactivation gating kinetic parameters were obtained by applying two exponential fitting of the deactivating currents at various extracellular chloride concentrations. It was found that decrease in extracellular chloride concentration increased the fractional amplitude of fast deactivating component, and depressed the fractional amplitude of slow deactivating component accompanied by a decrease in fast and slow deactivating time constants. These results demonstrate that the deactivation kinetic parameters of ClC-1 are largely dependent on the extracellular chloride concentration, which induces changes in channel gating.