GK大鼠胃转流术后空腹血糖及骨骼肌SIRT3酶变化的实验研究

目的:探讨GK大鼠行胃转流术后空腹血糖及骨骼肌SIRT3酶的变化及意义;方法:24只Goto-Kakizaki(GK)大鼠随机分为手术组(operation group OG组,假手术组(sim-operation group SG组)和对照组(control group CG组);OG组大鼠行胃转流手术,SG组大鼠行假手术,CG组仅作术前对照,OG组和SG组分别测定术前、术后48h和1、2及4周空腹血糖水平,术后4周处死取大腿部骨骼肌用western blot法半定量测定其SIRT3酶值;CG组监测空腹血糖水平,4周后处死同法测定大腿骨骼肌SIRT3酶值。结果:术前3组大鼠空腹血糖水平相仿,术后OG组血糖水平进行性下降,2周后血糖水平稳定,与SG组和CG组比较明显降低(P﹤0.05),SG组与CG组各时相空腹血糖水平差异无统计学意义(P﹥0.05);OG组术后骨骼肌SIRT3酶表达与明显增加,与SG组和CG组比较差异有统计学意义;结论:胃转流术可降低GK大鼠空腹血糖,骨骼肌SIRT3酶表达的增加可能是其糖尿病改善的机制之一。

Changes in fasting blood glucose and skeletal muscle SIRT3 enzyme in GK rats after undergoing gastric bypass operation

Objective: To investigate the changes in fasting blood glucose and skeletal muscle SIRT3 enzyme in GK rats after undergoing gastric bypass operation.Methods:Twenty-four Goto-Kakizaki(GK) rats were randomly divided into the operation group(OG group,n=8),sham group(SG group,n=8) and the control group(CG group,n=8).OG group were subjected to gastric bypass surgery,SG rats underwent a sham surgery,and CG group served as preoperative control.48 h and 1,2 and 4 weeks of fasting blood glucose levels of the OG group and SG groups were measured.Four weeks after the surgery,rats were sacrificed and the thigh skeletal muscle was taken out,semi-quantitative determination of SIRT3 levels were measured with western blot method.Results:The preoperative fasting glucose levels were similar among the three groups,after surgery,glucose level of OG group declined,and achieved stable 2 weeks later,showing significant difference from group SG and CG.(P<0.05).No significant difference in fasting blood glucose levels was observed between group SG and CG(P>0.05).The skeletal muscle SIRT3 enzyme expression level of the OG group were significantly increased compared with the SG group and CG group(P<0.05).Conclusion: The gastric bypass can reduce fasting blood glucose level in GK rats,increase in skeletal muscle SIRT3 enzyme expression might be one of the mechanisms by which diabetes can be improved.