维生素C对低硒高镉饲料饲养大鼠心肌细胞电生理的影响

目的:观察维生素C(VC)对低硒高镉饲料饲养大鼠心肌细胞电生理的影响。方法:用细胞内微电极技术分别观察了:普通饲料组对照、本实验构成饲料组对照、单纯高Cd、高Cd高VC、低Se高Cd、低Se高Cd伴高VC、高Se高Cd、高Se高Cd伴高VC饲料饲养14w后大鼠心肌细胞电生理的改变。结果:高Cd高VC组、高Se高Cd伴高VC组无变化;单纯高Cd组静息电位(RP)、动作电位幅度(APA)降低,动作电位时程(APD50、APD90)延长;低Se并高Cd组RP、APA降低,APD50、APD90明显延长;低Se高Cd高VC组、高Se高Cd组均表现为仅RP降低,APA、APD与对照组相比差异无显著性意义。结论:低硒并高镉饲料可明显改变大鼠心肌细胞的电生理特性,VC可以在一定程度上对抗这种变化。

EFFECTS OF VITAMINC ON THE ELECTROPHYSIOLOGICAL PROPERTY OF MYOCARDIAL CELLS OF THE RATS FED WITH LOW SELENIUM AND HIGH CADMIUM FODDER

Objective: To observe the effects of vitamin C(VC)on the electrophysiological property of myocardial cells of the rats fed with low selenium and high cadmium fodder. Method: Eight groups of rats were fed separately with: normal (2 groups), high Cd, high Cd high VC, low Se high Cd, low Se high Cd high VC, high Se high Cd and high Se high Cd high VC fodder for 14 w. With intracellular microelectrode technique, the electrophysiological changes of rats were observed. Results:Compared with the control, there were no changes in high Cd high VC group and in high Se high Cd high VC group. However,in high Cd group, RP and APA decreased, APD50 and APD90 prolonged; in low Se high Cd group ,RP and APA decreased, APD50 and APD90 prolonged significantly; in low Se high Cd high VC group and high Se high Cd group, though RP still decreased, no change had been detected on APA and APD. Conclusion: Se deficiency and simultaneous Cd overabundance may change the electrophysiological properties of myocardial cells of the rats significantly. However, VC may protect myocardial cells against the injury effectively.