AimTo investigate the effect of hydrogen sulfide (H₂S) on volume-regulated chloride channel (VRCC).MethodsH9c2 cardiomyocytes were cultured and treated with sodium hydrosulfide (NaHS, a H₂S donor).Expression of ClC-3 protein and VRCC chloride current (iCl-VRCC) were measured by Western blot assay and whole cell patch clamp, respectively.ResultsWhen H9c2 cardiomyocytes were placed in the isotonic solution, ICl was slightly activated.Hypotonicity obviously enhanced iCl (p<0.01), which was statistically attenuated by hypertonicity (p<0.05).ClC-3 protein was expressed in H9c2 cardiomyocytes.Similarly to the effect of isohytonicity on the activation of VRCC, treatment with 400 μmol/L NaHS for 0～30 min significantly increased iCl-VRCC (p<0.01), which was also statistically attenuated by hypertonicity (p<0.05).However, treatment with 400 μmol/L NaHS for 0～30 min did not alter the expression of ClC-3 protein in H9c2 cardiomyocytes (p>0.05).ConclusionsBoth VRCC and ClC-3 protein were expressed in H9c2 cardiomyocytes.H₂S activated VRCC in a ClC-3-independent manner.