TMEM16A氯通道对心肌缺血再灌注损伤的保护作用

Protective effect of TMEM16A chloride channel on myocardial ischemia reperfusion injury

目的探讨TMEM16A氯通道对心肌缺血再灌注损伤的保护作用。方法采用SD小鼠分离心肌细胞，分为4组，空白组正常培养细胞，模型组建立心肌缺血再灌注损伤模型，对照组在模型建立后采用Cl-free培养，实验组在模型建立后加入终浓度为0．1mmol／LTMEM16A氯通道抑制剂，记录和观察细胞存活率，GSH—Px、SOD、MDA、LDH酶活性变化及细胞内的Ca^2＋含量，TMEM16A、NF—KB表达变化情况。结果模型组与空白组比较细胞存活率降低、LDH升高（P〈0．05），对照组、实验组与模型组相比细胞存活率均升高，LDH均降低（P〈0．05）。模型组与空白组相比，细胞悬液中MDA含量升高，SOD、GSH—Px降低（P〈0．05），对照组、实验组与模型组比较细胞悬液中MDA含量降低，SOD、GSH—Px活性升高（P〈0．05）。空白组心肌细胞Ca^2＋含量为13．44±11．43，模型组为207．13±19．33，对照组和实验组为43．55±5．39和24．59±3．19，模型组最高（P〈0．05）。模型组的TMEM16A、NF—KB蛋白相对表达水平最高，其次为对照组，实验组和空白组最低，两两对比差异都有统计学意义（P〈0．05）。结论TMEM16A氯通道在心肌缺血再灌注损伤中起了重要作用，与增加细胞内氧化应激作用、NF—KB活性、细胞内Ca^2＋含量有一定的相关性。

Objective To investigate the protective effect of TMEM16A chloride channel on myocardial ischemia reperfusion injury. Methods The cardiomyocytes were isolated from SD mice and were divided four groups. The blank group was given normal cultured, the model group was used to establish the model of myocardial ischemia reperfusion injury, the control group was established by Cl-free cultured after the model was established, the experimental group was given the 0.1 mmol/L TMEM16A chloride channel inhibitor for cultured after the model was established, the cell survival rate, LDH, MDA, SOD, GSH-Px enzyme activity and intracellular the levels of Ca2＋ and the expression of NF-KB TMEM16A in the four groups were recorded. Results Compared with the blank group, the survival rate in the model group was significantly lower than that of the blank group, and the LDH was increased（P〈0.05 ）. Compared with the model group, the survival rate of the cells in the control group and the ex- perimental group was increased respectively, and the LDH were decreased （P〈0.05）. Compared with the blank group, the MDA levels in cell suspension was increased, SOD and GSH-Px decreased in the model group （P〈 0.05 ）, while levels of MDA in the cell suspension in the control group the experimental group were decreased, mid the activity of SOD and GSH-Px were increased （P〈0.05）. The levels of Ca^2＋ in the blank group was 13.44±11.43, and that in the model group was 207.13±19.33. The control group and the experimental group were 43.55± 5.39 and 24.59±3.19, respectively which were lower than that of the model group （P〈0.05）. The NF-KB, TMEM16A protein relative expression level in the model group was the highest, followed by the control group, the experimental group and control group were the lowest, there was statistically significant compared with two groups （P〈0.05）. Conclusion TMEM16A chloride channel in myocardial ischemia reperfusion injury played an important protective role, it has relationship with the increase of Ca2＋ levels, cell oxidative stress, NF-KB activity.