目的：观察十二指肠空肠旁路术（DJB）对2型糖尿病（T2DM）大鼠的治疗效果及机制。方法：将高脂饲料联合小剂量链脲佐菌素诱导的T2DM模型大鼠随机分为DJB组和假手术组，每组15只。观察2组大鼠手术前后体质量、空腹血糖及血脂的变化；于术后8周取DJB组大鼠Roux肠袢以及假手术组大鼠相应的肠组织标本，称重并用RT-PCR和Western blot检测参与糖代谢和脂代谢关键酶mRNA和蛋白表达。结果：术前两组空腹血糖、血脂水平、体质量均无统计学差异（均P>0.05）。术后DJB组与假手术组比较，空腹血糖水平与各血脂指标均明显降低（均P<0.05），但体质量无统计学差异（P>0.05）；Roux肠袢质量明显增加（2.025 g vs. 0.702 g），肠组织参与糖代谢和脂代谢关键酶的mRNA及蛋白水平均明显升高（均P<0.05）。结论：DJB能有效降低T2DM大鼠的血糖、血脂水平，该作用可能与术后小肠自身代谢的改变有关。
Therapeutic effect of duodenal-jejunal bypass on type 2 diabetes mellitus and the mechanism
Objective: To investigate the therapeutic effect of duodenal-jejunal bypass (DJB) surgery on type 2 diabetes mellitus (T2DM) in rats and the mechanism. Methods: Rats with T2DM induced by high-fat diet and low-dose streptozotocin injection were randomly divided into DJB group or sham operation group, with 15 rats in each group. The changes in body weight, fasting blood glucose and lipid profiles before and after operation in both groups were examined. At 8 weeks after operation, the specimens of intestinal Roux loop in rats of DJB group and corresponding intestinal segment in rats of sham operation group were harvested and weighed, and then the mRNA and protein expressions of the key enzymes involved in glucose and lipid metabolism were determined by RT-PCR and Western blot analysis. Results: There was no significant difference in fasting blood glucose and lipid levels and body weight between the two groups before operation (all P>0.05). In DJB group compared with sham operation group after operation, the fasting blood glucose level and each lipid index were significantly decreased (all P<0.05), but body weight showed no significant change (2.025 g vs. 0.702 g), the weight of intestinal Roux loop was significantly increased and both mRNA and protein levels of the key enzymes for glucose and lipid metabolism were significantly increased (all P<0.05). Conclusion: DJB can effectively reduce glucose and lipid levels in T2DM rats, and this effect may probably contribute to the alteration in metabolic patterns of the small intestine itself after operation.