汞对大鼠肾皮质线粒体ATP酶和膜电位的影响

Effects of mercury on ATPase and mitochondrial membrane potential in rat renal cortex

目的通过线粒体孵育液染汞并用N-乙酰半胱氨酸(NAC)干预研究汞对大鼠肾皮质线粒体损伤的影响。方法提取Wistar大鼠肾皮质线粒体液并分设为阴性对照组,5、50、500μmol/L氯化汞(HgCl2)直接染毒组及线粒体液NAC预处理后50μmol/L HgCl2染毒组5组。各组于培养箱内37℃孵育1 h后,测定Na+-K+-三磷酸腺苷(ATP)酶活力、Ca2+-ATP酶活力、线粒体膜电位及孵育液中细胞色素C含量。结果与阴性对照组比较,50、500μmol/L HgCl2染毒组Na+-K+-ATP酶、Ca2+-ATP酶活力及线粒体膜电位显著降低(P<0.05),细胞色素C含量显著升高(P<0.05);与50μmol/L HgCl2染毒组比较,NAC预处理后Na+-K+-ATP酶活力及线粒体膜电位显著升高,细胞色素C含量显著降低(P<0.05)。结论汞可以剂量依赖性地诱导大鼠肾皮质线粒体损伤,NAC预处理在某种程度上能有效地预防汞所致大鼠肾皮质线粒体损伤。

Objective To elucidate the effects of HgCl2 exposure on mitochondria in rat renal cortex and the preventive effects of N-acetylcysteine （NAC） in vitro. Methods Mitochondria from renal cortex were prepared and divided into 5 groups ： a control group ,5,50,500 μmol/L HgCl2 groups and a NAC pretreated-50 μmol/L HgCl2 group. All the groups were incubated at 37℃ for one hour. The activities of Na＋ -K ＋ -ATPase and Ca2 ＋ -ATPase, mitoehondrial membrane potential and the content of mitochondrial cytoehrome C were detected. Results Compared with the control group, the activity of ATPase and mitochondrial membrane potential in 50 and 500 μmol/L HgCl2 groups were decreased （P 〈 0. 05 ） , the content of mitochondrial cytochreme C was increased （ P 〈 0. 05 ）. While compared with 50 μmol/L HgC12 group, in the NAC pretreated group, the activity of Na＋ -K＋ - ATPase and the mitochandrial membrane potential were increased （ P 〈 0.05 ） , the content of mitochondrial cytochrome C was decreased （ P 〈 0. 05 ）. Conclusion HgCl2 could dose-dependently induce the damage of mitochondria from renal cortex in rats ; this change could be prevented by pre-treating with NAC to some extent.