摘要
目的:探讨不同浓度胰岛素对钙超载心肌细胞葡萄糖摄取的量效关系.方法:采用伊屋诺霉素构建不同程度成年大鼠心肌细胞钙超载模型;应用同位素示踪技术观察不同浓度(0,0.01,20 U/L)胰岛素刺激大鼠心肌细胞的葡萄精摄取效应,评价钙超载后心肌细胞的葡萄糖摄取与胰岛素剂量之间的关系.结果:心肌细胞活性比率分别为73.0±2.4,70.5±2.0(P>O.05).对照组心肌细胞静息[ca~(2+)]i为(115 ±21)nmol/L,经伊屋诺霉素(1.0 μmol/L)处理1 h,实验组心肌细胞[Ca~(2+)]i为(376±29)nmol/L(P<0.05).对照组不同浓度的胰岛素(0,0.01,20 U/L)刺激心肌细胞葡萄糖摄取30min,心肌细胞葡萄糖摄取分别为(18±9)Ixmolf(10~5 cells·10 min),(32 ±6)μmol/(10~5 cells·10 min),(54±10)μmoL/(10~5 cells·10 min),实验组不同浓度的胰岛素(0,0.01,20U/L)刺激心肌细胞葡萄糖摄取30 min,心肌细胞葡萄糖摄取分别为(14±7)μmol/(10~5 cells·10 min),(18 ±4)μmol/(10~5 cells·10 min),(26±9)μmol/(10~5 cells·10 min)(组间P<0.05).结论:钙超载心肌细胞葡萄糖摄取能力降低,但保留了胰岛素的反应性.胰岛素能促进钙超载心肌细胞的葡萄糖摄取,并呈剂苗依赖关系.
Abstract
AIM:To initially investigate the association of elevated insulin stimulated glucose uptake in cardiomycytes during calcium overload.METHODS:111e calcium overload model in cardiomyoctyes was developed by using ionomycin.The glucose uptake of cardiomyoctyes stimulated by insulin was detected with isotopic tracer technique.RESULTS:After calcium overload,cardiomyocyte viability did not decrease significantly(P>0.05,vs control).Cytosolic calcium of cardiomyocytes(ionomycin 1.0 μmol/L)was higher than that of control cardiomyocytes[(376±29)vs(115±21)nmol/L,P<0.05].Insulin stimulated glucose transport into cardiomyocytes.Glucose uptake in 20 U/L insulin group are higher than that in 0.01 U/L insulin group(P<0.05).CONCLUSION:Cardiomyocytes during calcium overload hold responsiveness to insulin,but at the same time,with different concentrations insulin,cardiomyocytes glucose uptake gradually increased during calcium overload.
NETL
NSTL
维普
万方数据