Effect of Roux-en-Y gastric bypass surgery and exogenous insulin administration on type 2 diabetic rats

Objective:To compare effect of gastric bypass surgery(GBP)and exogenous insulin treatment on type 2diabetic rats.Methods:Type 2diabetic model of 67rats was established by intraperitoneal injection of chain urea via cephalosporins way.Then they were randomly divided into control group,insulin group and GBP group.Weight,fasting plasma glucose and fasting c-peptide were measured before operation,1week,4weeks,12weeks after surgery.They were killed 12weeks after surgery.Insulin immunohistochemical analysis was performed.Islet number and islet secretion were also observed.Results:There was significant difference in weight between GBP group and control group insulin group4,12week after surgery(P0.05).In GBP and insulin group postoperative fasting glucose were significantly decreased(P0.05).4,12weeks after surgery,fasting C peptide in GBP and insulin groups was significantly higher than that of control group(P0.05).And 12weeks after surgery,fasting c-peptide of GBP group was significantly higher than that of insulin group(t=5.407,P0.05).After 12weeks,the average islet number of GBP group was significantly higher than that of control group and insulin group(P0.05);12weeks after surgery,average grey value of GBP group was significantly lower than that of control group and insulin group(P0.05).Conclusions:Type 2diabetic rats with gastric bypass surgery treatment have islet cell hyperplasia in the short term,and insulin secretion was improved.The effect is more significant than that of exogenous insulin.However,the long-term curative effect still need further research.