硒缺乏对大鼠心肌细胞凋亡的影响及褪黑素的干预作用

目的　探讨低硒与心肌细胞凋亡的关系及褪黑素能否保护心肌免于低硒所致的心肌损伤。方法　对低硒粮喂养、加硒喂养及低硒粮加褪黑素喂养三组大鼠的心肌组织丙二醛水平及细胞凋亡进行检测和对比分析。结果　大鼠饲养 12周后 ,低硒组大鼠心肌组织丙二醛水平较加硒组和低硒 +褪黑素组显著升高 (P <0 .0 1) ;加硒组和低硒 +褪黑素组两组间无显著差异 (P >0 .0 5 ) ;低硒、加硒及低硒加褪黑素喂养大鼠 3组间心肌细胞凋亡检出率分别为 7/ 8,2 / 8,1/ 8,后两组与低硒组相比有显著性差异 (P <0 .0 5 )。结论　低硒导致的脂质过氧化物损伤可能参与诱发心肌细胞凋亡 ,褪黑素则有减轻作用 ,其机制可能与褪黑素的抗氧化作用有关。

Effect of low-selenium diet on apoptosis of cardiac myocytes in rats and melatonin's protective effects

Objective To investigate the relationship betwe en low-selenium diet and apoptosis of cardiac myocytes in rats and if melatonin c an have protective effects on the damage. Methods The level of myocardial MDA in rats' was measured a nd apoptosis of cardiac myocytes in rats was detected in the three groups of rat s, fed with low-selenium diet, sufficient-selenium diet and low-selenium diet plus intragastric administration of melatonin, respectively. Results The level of MDA in myocardium was significantly hi gher in low-selenium group than that in sufficient-selenium group and low-sel enium group with intragastric administration of melatonin (P<0.01); the rate of apoptosis of cardiac myocytes detected in the three groups was 7/8, 2/8 and 1/8 respectively; the rate of apoptosis of myocardial cells detected in low-sel enium diet group was higher than that in the other two groups as well (P< 0 .05). Conclusion The accumulation of lipid peroxidized products c aused by insufficient-selenium diet may be associated with the development of a poptosis of myocardial cells. Melatonin can decrease the degree of apoptosis of myocardial cells, which is probably due to its anti-oxidizative action.