H2S-Mediated Changes in Erythrocyte Volume: Role of Gardos Channels, Na+,K+,2Cl— Cotransport and Anion Exchanger

The effect of H2S on changes in erythrocyte volume was studied by spectrophotometrical and potentiometric methods. It was found that H2S donor NaHS (2.5, 10, and 100 μM) induced an increase in erythrocyte volume in heterosmotic media. Activation of Gardos channels with A23187 or ascorbate—phenazine methosulfate system causes erythrocyte shrinkage and hyperpolarization of their membrane, while addition of NaHS restored erythrocyte volume. The decrease in erythrocyte volume upon blockade of Na+,K+,2Cl— cotransporter (bumetanide) or anion exchanger (SITS) was abolished by H2S donor NaHS, which attested to an important role of these transporters and chlorine conductivity of the membrane in the maintenance of the homeostasis of blood cells.