The effect of duodenal-jejunal bypass on the expression of ileum proglucagon mRNA in Goto-Kakizaki type 2 diabetic rats

Objective To investigate the effect of duodenal-jejunal bypass(DJB) on glucose metabolism and the expression of ileum proglucagon mRNA in Goto-Kakizaki (GK) type 2 diabetic rats.Methods 18 male GK rats and 1 8 male Wistar rats were randomly divided into 4 groups:GK operation group(group A),GK sham operation group(group B),Wistar operation group (group C),Wistar sham operation group (group D).There were 9 rats in each group.The fasting blood glucose and GLP-1 levels were measured before and at the 8th weekafter surgery.Oral glucose tolerance test was measured,and the area under blood glucose concentration curve wascalculated.Ileum tissues were obtained 8 weeks postoperatively and reverse transcriptase polymerase chain reac-tion was used to detect ileum PG mRNA expression after the operation.Results At the 8th week after surgery,the fasting blood glucose of group A decreased from(8.73 ± 1.30) mmol/L to(5.86 ±0.57) mmol/L(P ＜0.05).Area under blood glucose concentration curve decreased from preoperative(60.23 ± 5.14)mmol · h/L to (47.80 ±1.79) mmol· h/L(P ＜ 0.05).Fasting serum GLP-1 in group A increased from (7.69 ± 0.74) pmol/L to (29.00 ±4.85) pmol/L while postprandial GLP-1 increased from(15.74 ± 5.71) pmol/L to (45.78 ± 7.26) pmol/L (P ＜0.05).At the 8th week after surgery,the ileum PG mRNA level in group A was significantly higher than that in group B(P ＜ 0.05).Conclusions DJB can directly improve glucose metabolism in non-obese type 2 diabetic rats,and the operation has no hypoglycemic effect on normal blood glucose.The increased expression of ileum PG mRNA might contribute to the hypoglycemic effect of the surgery. Key words: Duodenal-jejunal bypass;  Type 2 diabetes mellitus;  Goto-Kakizaki rats;  Glucagonlike peptide-1; Proglucagon