Activation of chloride channels in the plasmalemma of <i>Nitella syncarpa</i> by inositol 1,4,5‐trisphosphate

Abstract

The introduction of 1.5 × 10 −8 − 10 −6 M inositol 1,4,5‐trisphosphate (IP 3 ) into the bathing solution of Nitella syncarpa cells induced: (i) an increase in amplitude of the inward Ca 2+ current; (ii) the appearance of an inward Cl − current; (iii) a shift in the threshold for activation of the Cl − channels on hyperpolarization of the membrane to more positive values. These facts suggest that IP 3 participates in the causing of changes in the intracellular free Ca 2+ concentration and, hence, in the regulation of ionic channels in Nitella syncarpa plasmalemma.