Roux-en-Y胃旁路术对GK大鼠糖代谢的持续性改善作用

Continuous glycometabolism improvement by Roux-en-Y gastric bypass surgery in GK rats

目的研究Roux-en-Y胃旁路术(RYGB)对自发性2型糖尿病GK大鼠糖代谢的持续性改善作用及可能的作用机制。方法 24只雄性GK大鼠随机分为RYGB手术组、假手术饮食控制组、空白对照组(n=8),以Wistar大鼠作为正常对照组(n=8)。定期测量大鼠体质量;在术后1、3、6个月时,对各组大鼠行口服糖耐量试验;术后6个月时,对各组大鼠行静脉注射糖耐量试验并检测血浆胰岛素含量,处死各组大鼠后检测血浆游离脂肪酸和三酰甘油含量,Western blotting检测肝脏组织中胰岛素受体的表达。结果 RYGB手术组大鼠术后体质量控制良好,术后6个月时的体质量显著低于其他各组(P<0.05)。术后1、3、6个月的口服糖耐量试验及术后6个月的静脉注射糖耐量试验结果表明,RYGB手术组各项指标均优于假手术饮食控制组和空白对照组。术后6个月,RYGB手术组血浆游离脂肪酸和三酰甘油含量显著低于假手术饮食控制组和空白对照组(P<0.05),而肝脏组织中胰岛素受体的表达显著高于假手术饮食控制组和空白对照组,差异均有统计学意义(P<0.05)。结论RYGB对GK大鼠的糖代谢具有持续性改善作用,可能与血浆游离脂肪酸和三酰甘油水平的降低而使胰岛素抵抗缓解并促进胰岛功能恢复有关。

Objective To explore the mechanism of continuous glycometabolism improvement by Roux-en-Y gastric bypass （RYGB） surgery in GK rats. Methods Twenty-four male GK rats were randomly divided into RYGB surgery group, sham operation diet control group and blank control group, with 8 rats in each group. Besides, 8 Wistar rats were served as normal control group. The body weight of rats was measured regularly. Oral glucose tolerance tests were performed 1, 3 and 6 months after surgery in all groups. Six months after surgery, intravenous glucose tolerance test was performed, and plasma insulin was detected in each group. Plasma free fatty acids and triglyceride were determined after the rats were sacrificed 6 months after surgery, and the expression of insulin receptor in the liver was detected by Western blotting. Results The body weight of rats in RYGB surgery group was well controlled after surgery, and the body weight of rats in RYGB surgery group was significantly lower than that in the other groups 6 months after surgery （P 〈 0.05）. Oral glucose tolerance tests 1, 3 and 6 months after surgery and intravenous glucose tolerance test 6 months after surgery demonstrated that all the parameters in RYGB surgery group were superior to those in sham operation diet control group and blank control group. Six months after surgery, plasma free fatty acids and triglyceride in RYGB surgery group were significantly lower than those in sham operation diet control group and blank control group （ P 〈 0.05）, while the expression of insulin receptor in the liver in RYGB surgery group was significantly higher than that in sham operation diet control group and blank control group （P 〈 0.05）. Conclusion RYGB surgery plays a role in the continuous glycometabolism improvement in GK rats, which maybe associated with the relief of insulin resistance and restoration of islet function promoted by decreased plasma free fatty acids and triglyceride.