Effect of gastric bypass surgery on fasting blood-glucose and glucagon-like peptide-1 in type 2 diabetic rats

Objective To investigate the effect of gastric bypass surgery (GBP) on fasting bloodglucose (FBG) and glucagon-like peptide-1 (GLP-1) in type 2 diabetic rats.Methods The models of type 2 diabetic rats were induced by stretozotocin and 20 diabetic rats were randomly divided into two groups:diabetes-operation group ( DO group,n =10) and diabetes-control group ( DC group,n =10).Another twenty normal rats were randomly divided into two groups:normal-operation ( NO group,n =10)and normal-control group ( NC group,n =10).The FBG levels and glucagon-like peptide-1 ( GLP-1 ) concentrations of rats in each group were detected before operation and 72 h,on 1 week,4 weeks,8 weeks after operation.Results The FBG levels of rats before operation were not statistically significant different between DO group and DC group or between NO group and NC group ( P ＞ 0.05 ).After operation,the FBG levels of rats in DO group gradually declined,eight weeks after operation the FBG levels was declined from ( 20.84 ± 1.98 ) mmol/L to (5.56 ± 0.11 ) mmol/L ( P ＜ 0.05 ) ; In DC group,the difference of FBG levels of rats at different time point was not statistically significant (P ＞ 0.05).After operation,the concentrations of serum GLP-1 of rats in DO group and NO group gradually increased,eight weeks after operation The serum GLP-1 elevated respectively from (7.10 ± 0.55 ),( 10.73 ± 0.67) pmol/L to ( 26.48 ±1.14),( 13.98 ±0.92) pmol/L (P ＜0.05).Conclusion There is obvious hypoglycemic effect of GBP on FBG levels of type 2 diabetic rats other than normal rats,in which high secretion of GLP-1 may be play an important role,high secretion of GLP-1 on the normal type 2 diabetic rats has no hypoglycemic effect. Key words: Type 2 diabetes ;  Gastric bypass ;  Glucagon-like peptide-1