褪黑素对心肌细胞氧化损伤的保护作用

目的 :探讨褪黑素 （MT）对过氧化氢 （H2 O2 ）损伤乳鼠心肌细胞的保护作用。方法 :胰酶消化法分离培养原代心肌细胞 ,用生化法检测培养液中乳酸脱氢酶 （L DH）浓度 ,台盼蓝排斥试验检测细胞存活率 ,硫代巴比妥酸法测定细胞中丙二醛 （MDA）含量。结果 :10 0 μmol/ L 的 H2 O2 使培养液 L DH漏出量和心肌细胞中 MDA含量明显增加 （分别为 6 .5± 1.6 vs 2 4.8± 1.7U / m l和 1.2 3± 0 .0 5 vs 3.6 5± 0 .2 0 nmol/ 10 6 cells,P<0 .0 1） ,心肌细胞存活率明显下降 （96 .0 %± 1.8% vs 6 0 .0 %± 3.2 % ,P<0 .0 1）。加入 MT后 ,培养液 L DH漏出量和细胞 MDA含量明显降低（分别为 10 .2± 1.3U / ml和 1.5 9± 0 .0 9nm ol/ 10 6 cells） ,细胞存活率明显增高 （90 .0 %± 2 .2 % ） ,与 H2 O2 处理组相比均有显著差异 （均 P<0 .0 1）。结论 :MT能对抗过氧化氢所致的心肌细胞损伤 ,其保护作用与其抗氧化作用有关。

Antioxidant effects ofmelatonin on cultured rat cardiomyocytes

AIM:To investigate the effects of Melatonin (MT) on cardiomyoc ytes dam aged by H2O2. METHODS: The rat cardiomyocytes were cultured in DMEM for 4～5 day s. Cultured cells were divided into three groups randomly: control group, H2O 2 g roup and MT group. The leakage of lactate dehydrogenase (LDH) was assayed by aut omatic biochemical analyzer. The content of malondialdehyde (MDA) was determined by measuring thiobarbituric acid-reactive substances. RESULTS: Compa red with th ose of the control group, both LDH leakage and MDA content increased significant ly(from 6.5±1.6 U/ml to 24.8±1.7 U/ml, and from 1.23±0.05 nmol/106 cells to 3.65±0.20 nmol/106 cells,P<0.01),cell viability decreased significan tly(from 96.0%±1.8 % to 60.0%±3.2%, P<0.01). In MT group, MT inhibited the increase of LDH leakage and MDA content induced by H2O2 (10.2±1.3 U/ml and 1.59±0.09 nmol/106 cells res pectively) and increased the cell viability(90.0%±2.2%). CONCLUSION: MT can prote ct the cardiomyocytes against H2O2 induced injury with its antioxidative ef fect.