脂质过氧化对培养心肌细胞肌球蛋白轻链磷酸化系统的影响

应用氢过氧化枯烯（ＣＨＰＯ）作为机体产生自由基的引发剂，作用于培养的心肌细胞，激起和促使细胞遭受过氧化损伤，同时使用硒（Ｓｅ）、维生素Ｅ（ＶＥ）等抗自由基物质，观察细胞中肌球蛋白轻链磷酸化系统的变化。结果表明，ＣＨＰＯ引发的自由基以及脂质过氧化反应，造成肌球蛋白轻链激酶（ＭＬＣＫ）和ＡＴＰ酶活性显著下降，Ｓｅ、ＶＥ以及二者联合应用，可使心肌细胞抗自由基损伤的能力极大增强，ＭＬＣＫ和ＡＴＰ酶活性都有不同程度的提高。提示：ＣＨＰＯ引发的自由基已造成了对心肌细胞肌球蛋白磷酸化系统的损害，Ｓｅ和ＶＥ的应用，对保护肌球蛋白分子的完整结构和其生化功能起着重要作用。

Effects of lipid peroxidation on the phosphorylation of myosin light chains in the cultured cardiac cells

Cumene hydroperoxide(CHPO)is the inducer of free radical production in vi-vo. Investigations were made on the cultured cardiac cells with CHPO supplement.The results showedthat the activity of MLCK in cultured cardiac cells with CHPO(0.34 ± 0.067)was much lower thanthat of the control group(0.92± 0.14)(P<0.01).Meanwhile the ATPase activity also significantlydecreased.In the presence of Se and VE,activities of MLCK and ATPase in injured cells increase. It issuggested that Se and VE could protect cardiac cells from radical injury by preventing chaints reactionof radicals and clearing out lipid peroxides,and Se and VE might play significant roles in the treatmentand prevention of some cardiac diseases.