Effects of Roux-en-Y operations on glucose homeostasis in obese GK rats

Abstract: Aim: To investigate the therapeutic effects of different styles of gastric bypass surgery on type 2 diabetes mellitus (T2DM) GK rats. Methods: Twenty 6–8-week-old male GK rats were randomly divided into four groups: group A was operated by Roux-en-Y gastrojejunostomy with duodenum exclusion and stomach capacity maintenance, group B was operated by loop-type gastrojejunostomy with duodenum exclusion and stomach capacity maintenance, group C was operated by Roux-en-Y gastrojejunostomy with partial gastrectomy, and group D was operated by loop-type gastrojejunostomy with partial gastrectomy. Changes of fasting blood glucose, oral glucose tolerance test (OGTT), and insulin tolerance test (ITT) in different operations were detected. Results: The operations exerted good effects on controlling blood glucose in groups A, B, C, and D. There was no significant difference between groups A and C (P > 0.05) or between groups B and D (P > 0.05), while operations in groups A and C were more effective than groups B and D (P < 0.05). On the 21st day after surgery, OGTT in animals of groups A and C was significantly improved, as indicated by a 34% reduction in the area under the curve (AUC) for blood glucose (P < 0.05 versus groups B and D); pregavage insulin levels (ng/ml) were significantly decreased in groups A and C (P < 0.05 versus groups B and D). The insulin tolerance test (ITT) confirmed impaired insulin sensitivity in groups B and D, compared with groups A and C. Conclusions: Gastric bypass surgery might be effective to treat type 2 diabetes mellitus (T2DM), and Roux-en-Y gastrojejunostomy might be more effective than other operative styles.