The Antidiabetic Effect And GLP-1Secretion Of Roux-en-Y Gastric Bypass On Type2Diabetes Rats

Objective:To investigate effect of RYGBP on Diabetic Rat induced by STZ injection and explore mechanisms involved.Methods:STZ were injected intraperitoneally into male Sprague Dawley (SD) rats to establish diabetic animal model.64diabetic rats were randomly divided into4groups:operation group(Group O), sham operation group(Group S), food control group(Group F) and control group(Group C). Weight, fasting blood glucose, Fasting plasma insulin and GLP-1were measured1,2,4and8weeks after operation.Results:1.Body weightBody weight of Group O, Group S and Group S started decreasing1week after operation. Body weight of Group O and Group F lost significantly (P<0.05). Body weight of Group O decreased to (345.6±13.2) g,(P<0.05). Weight loss in Group F was similar with that in Group O and there was no statistical difference between these2groups (P>0.05). body weight of Group S and C had no statistical change comparing to preoperative weight.2. Fasting blood glucose (FBG)FBG in Group O started dropping1week after operation and it reached (15.7±3.1) mmol/L2week after operation which was significantly lower, comparing to FBG before operation(20.5±2.1mmol/L).8weeks after operation it further reduced to (8.2±2.4) mmol/L(P<0.05). FBG in Group F4and8weeks after operation were (15.1±3.2) mmol/L and (13.4±2.9) mmol/L respectively, which has statistical difference comparing to that prior to diet control. FBG in Group O was significantly reduced comparing to that in Group4weeks after operation. There was no difference between Group S and C.3. Fasting plasma insulin(FPI) FPI in Group O increased after operation and reached (72.5±7.4) mU/L at Week8which showed significant elevation comparing to the value of (29.1±5.1) mU/L prior to operation. FPI in Group4gradually increased from Week4, and reached the maximal value of (50.3±5.7) mU/L (P<0.05) at Week8. FPI in Group O was statistically higher than that in Group F (P<0.01). There was no difference between Group S and C(P>0.05).4.GLP-1GLP-1in Group O started to rise at Week1after operation. At week2it was elevated from the preoperative value of (8.69±2.02) pmol/L to (12.51±1.75) pmol/L (P<0.05) Till8weeks after operation, it was (23.26±2.19) pmol/L (P<0.05)5.Relevance of blood glucose, insulin and GLP-1in Group OBlood glucose in Group O showed statistical negative relation with insulin and GLP-1(r=-0.833and r=-0.758, P<0.05). And GLP-1was positive relevant with insulin (r=0.885, P<0.05)Conclusion:1. RYGBP was an effective therapy to control blood glucose in type2diabetic rats.2. RYGBP can lead to high secretion of GLP-1.3. There is no significant relation between type2diabetic rats blood glucose decreased and restricted diet and weight loss after RYGBP.