H2S and HS- donor NaHS inhibits intracellular chloride channels

Abstract

We have characterized the effect of H2S on single channel properties of the chloride channels derived from the rat heart lysosomal vesicles incorporated into a bilayer lipid membrane. The single chloride channel currents were measured in 250:50 mmol/l KCl cis/trans solutions. H2S inhibited the chloride channels by decreasing the channel open probability in a concentration-dependent manner. The inhibitory effect of H2S was side-dependent with the IC50 values of 42 and 75 μmol/l for the trans and the eis sides, respectively. The mixture of H2S with the NO donor S-nitroso-N-acetyl-DL-penicillamine had smaller effect (IC50 = 180 μmol/l) than H2S alone. We assume that the inhibitory effect of H2S on chloride channels may be responsible for some of its numerous biological effects.