Gastric Bypass On Type2Diabetes And Itsinitial Mechanisms

Objective:To evaluate the effect of Roux-en-Y Gastric Bypass (RYGB) and Mini-gastric bypass (MGB) on STZ-induced type2diabetic rat model to clarify its primary mechanism.Methods:40rats of type2diabetic were randomly allocated into four groups on average:Mini-gastric bypass group (MGB group),10rats; Roux-en-Y Gastric Bypass group (RYGB group),10rats; diet control group (DC group),10rats; blank control group (BC group),10rats. The fasting blood glucose, the fasting plasma IGF-1, the fasting plasma Ghrelin, the fasting plasma Cholecystokinin (CCK), the weight, the food-intake, the operation time and the death rate were measured in preoperative and postoperative1,2,3,4,8and12weeks, respectively.Results:The fasting blood glucose of the group MGB descend to10.7±3mmol/L in the4th week after operation, the fasting plasma insulin rose up to43.5±4.2mU/L in the2th week after operation. The weight descend to202±12.2g in the12th week after operation. Ghrelin and IGF-1levels were higher than the preoperative. In the2th week after operation CCK levels was significantly higher than before. There were significant differences between before and after operation (P<0.05). The fasting blood glucose of the group RYGB descend to10.3±2.5mmol/L in the4th week after operation, the fasting plasma insulin rose up to49.5±9.2mU/L in the2th week after operation. The weight descend to200±15.9g in the12th week after operation. Ghrelin and IGF-1levels were higher than the preoperative. In the2th week after operation CCK levels was significantly higher than before. There were significant differences between before and after operation (P<0.05). There were not significant differences of the fasting blood glucose, fasting plasma insulin and the food-intake between group MGB and group RYBG after operation (P>0.05); There were significant differences of the IGF-1, the Ghrelin, and CCK. Compared the fasting plasma insulin and the weight of rats between group MGB and group RYBG after operation, there were significant differences (P<0.05). There were significant differences of the operation time and the death rate between group MGB and group RYBG after operation (P<0.05).Conclusion:The group of MGB and the group of RYGB can improve the fasting blood glucose at the early stage, more effectively than the group of DC and BC. Diet control and changes of fasting plasma insulin and Ghrelin in different levels may be the mechanisms to improve fasting blood glucose in the group RYGB and MGB. The IGF-1increased in The group MGB and the group RYGB after operation, suggesting that the change of IGF-1may be an important mechanism of improve fasting blood glucose model after Roux-en-Y gastric bypass and Mini-gastric bypass in STZ-induced type2diabetic rat. The different levels of CCK results from reduction in food intake after surgery. In the operation time and die rate, the group MGB surpass the group RYGB.