硫化氢激活H9c2心肌细胞容积调节性氯通道

Hydrogen Sulfide Activated Volume-Regulated Chloride Channel in H9c2 Cardiomyocytes

目的观察硫化氢(H2S)对H9c2心肌细胞容积调节性氯通道(VRCC)的影响。方法培养大鼠H9c2心肌细胞,用H2S供体硫氢化钠(NaHS)处理H9c2心肌细胞。分别应用Western blot和全细胞膜片钳技术分析蛋白的表达和VRCC的开放和关闭。结果等张灌流液处理的H9c2心肌细胞可记录到微弱的背景氯电流。低张灌流液处理可明显增加H9c2心肌细胞的氯电流(P<0.01),高张灌流液处理则可减弱这种增强作用(P<0.05)。Western blot检测显示H9c2心肌细胞上存在ClC-3氯通道蛋白的表达。用400μmol/L NaHS处理0～30 min可激活H9c2心肌细胞上的氯通道,高张灌流液处理抑制NaHS处理诱导的氯通道激活。400μmol/L NaHS处理0～30min对H9c2心肌细胞ClC-3氯通道蛋白的表达无明显影响(P>0.05)。结论 H9c2心肌细胞存在VRCC和ClC-3氯通道蛋白的表达,H2S处理可激活VRCC而不影响ClC-3氯通道蛋白的表达。

Aim To investigate the effect of hydrogen sulfide（H2S） on volume-regulated chloride channel（VRCC）.Methods H9c2 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.Results When H9c2 cardiomyocytes were placed in the isotonic solution,ICl was slightly activated.Hypotonicity obviously enhanced ICl（P0.01）,which was statistically attenuated by hypertonicity（P0.05）.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（P0.01）,which was also statistically attenuated by hypertonicity（P0.05）.However,treatment with 400 μmol/L NaHS for 0~30 min did not alter the expression of ClC-3 protein in H9c2 cardiomyocytes（P0.05）.Conclusions Both VRCC and ClC-3 protein were expressed in H9c2 cardiomyocytes.H2S activated VRCC in a ClC-3-independent manner.