【摘要】 目的   探讨不同病程T2DM大鼠胸主动脉上大电导钙激活通道(BKca)蛋白及mRNA表达的变化。 方法   60只大鼠被随机分成对照(Con)组10只和模型(M)组50只。Con组予常规饲养，M组采用高脂高糖饮食且腹腔注射小剂量STZ建立T2DM大鼠模型。免疫印记法和RT-PCR测定胸主动脉BKa通道α，β1 亚单位的蛋白和rnRNA表达水平。 结果8周、12周M组BKca亚单位蛋白在胸主动脉中的表达为(0.942±0.324)和(0.925±0.521)；BKa-12亚单位mRNA表达为(0.93±0.03)和(0.92±0.07)。(2)8周、12周M组Brat3l亚单位蛋白在胸主动脉中的表达为(0.452±0.25)和(0.401±0.34)；BKcaβ1l亚单位mRNA表达为(0.56±0.19)和(0.43±0.06)。与Con组比较，8周、12周M组岛亚单位蛋白和mRNA表达降低(P＜0.05)。 结论   T2DM大鼠大血管上BKa通道岛亚单位蛋白及mRNA的表达在8周及12周降低。
   【关键词】  糖尿病，2型；BKca通道；α，β1，亚单位；表达变化

    【Abstract】  Objective  To explore the expression changes of a and 131 protein and mRNA of BKc．channel in thoracic aorta in type 2 diabetic(T2DM)rats at different courses． Methods   60 rats wererandomly divided into normal control group(Con，n＝10) and model group (M，n=10)．The rats in Con group were fed with common diet．Diabetes was induced by feeding with high fat and sucrose diet plus intraperitoneal injection of STZ in Mgroup．Western blot and real-time PCR were taken to detect α and β1protein and mRNA expression levels． Results   (1)a subunit protein expression of BKca channel in M group at 8 weeks and 12 weeks were (0.942±0.324) and (0.925±0.521) respectively；a subunit mRNA expression were (0.93±0.03) and (0.92±0.07)．(2)B1 subunit protein expression of BKachannel in M group at 8 weeks and 12 weeks were(0.452±0.25) and (0.401±0.34)；β1 subunit mRNA expressionwere (0.564±0.19) and (0.43±0.06)．β1 subunit protein and mRNA expression of BKca at 8 weeks and 12 weeks in Mgroup were lower than that in Con group(P<0.05)． Conclusion   β1 subunit protein and mRNA expression of BKca channel in thoracic aorta are 10 wered significantly inT2DM rats at 8 weeks and 12 weeks．
    【Key words】 Diabetes mellitus，type 2；BKc．channel；a，Bl subunit；Expression changes