Effect Of Roux-en-Y Gastric Bypass With Different Gastric Volume In Non-obese Rats With Type2Diabetes

【Objective】To study the relationship between the size of the stomach volume and glycemic control byestablishing Roux-en-Y gastric bypass surgery with different volumes of remnant inGoto-Kakizaki rats. Our pilot study may provide a possible mechanisms for the glycemiccontrol and the surgical improvements in which are involved the improvement of glucoseregulation after Roux-en-Y gastric bypass surgery.【Methods】48male Goto-Kakizaki rats (a standard model of T2DM) were categorized randomly intofour groups: group A (n=12) underwent Roux-en-Y cardia-jejunal anastomosis with totalstomach, duodenum and proximal jejunum exclusion, group B(n=12) underwent Roux-en-Ygastrojejunostomy with subtotal stomach, duodenum and proximal jejunum exclusion, groupC(n=12) underwent Roux-en-Y gastrojejunostomy with duodenum and proximal jejunumexclusion and stomach capacity maintenance, Group D(n=12)underwent sham-operation(incision of the stomach and intestinal and the anastomosis in situ). All rats were observed for24weeks after surgery. Fasting plasma glucose, average daily food intake, body weight,complication and mortality after operation were observed before surgery (0week) and1,4,8,12,24week postoperatively. Hemoglobin A1c (HbA1c) level was measured at0,4,12,24week. Oral Glucose Tolerance Test was performed at0，12and24week. Blood glucose wasmeasured in conscious rats before（baseline）and after15，30，60，90and120minutes. Oralglucose tolerance areas under curves （AUC）were calculated by trapezoidal integration andpeak blood sugar（30min）was observed.【Results】1. Related Indicators of Glucose Metabolism There were no significant differences ofFPG, HbA1c, AUC and peak blood sugar (30min) among four groups preoperatively (P>0.05). Compared with pre-operation, the fasting plasma glucose was significantly decreased aftersurgery on the Roux-en-Y gastric bypass groups (Group A, Group B and Group C)(P<0.01),and remained steady for four weeks after surgical procedure. These three groups all showed amild reduction of HbA1c4weeks postoperatively without statistically significant (P>0.05).FPG and HbA1c decreased distinctly in group A, group B and group C compared with baselinevalues during the entire follow-up period(P<0.05). Oral glucose tolerance area under the curve(AUC) and oral glucose tolerance peak blood sugar (30min) in group A, group B and group Cwere significantly less at12and24weeks after surgical procedure(P<0.01).AUC decreasedrespectively in group A,group B and group C by52.66%,50.00%and46.17%. Compared withpre-operation, related indicators of glucose metabolism in group D has no significantly changesafter operation (P>0.05). FPG, HbA1c, AUC and peak blood sugar (30min) in group A, groupB and group C were distinctly lower than group D’s (P<0.05) at1,4,8,12,24week afteroperation. There were no significant differences among the Roux-en-Y gastric bypass groups(Group A, Group B and Group C) during follow-up period at the same time (P>0.05).2. Average Daily Food Intake and Body Weight There were no significant differencesof food intake and body weight among four groups preoperatively (P>0.05). Compared withpre-operation, food intake and body weight in each group were significantly decreased at1week after surgical procedure (P<0.05). Food intake and body weight in each group weregradually increased during the entire follow-up period and maintained a stable level at12,24weeks after surgical procedure.Food intake and body weight of group A at24weeks after surgery were lower than thepreoperative (P>0.05), while Group B, C and D groups were higher than preoperative levels(P>0.05). The added value of group A and group B were lower than the group C and group D.Food intake and body mass of group A and group B were lower than group C and group D, andthe differences were statistically significant (P<0.05), howere, no distinct differences werefound when compared in group A and group B or group C and group D at1,4,8,12,24week.3. Complications and Mortality All rats in each group did not appear the phenomenonof anesthesia accidents, hemorrhagic shock, cardiac arrest and respiratory pause during surgicalprocedures. The postoperative rats in each group were varying degrees of malnutrition,diarrhea and other complications. And the mortality of the four groups was0%. 【Conclusions】1. The Roux-en-Y gastric bypass with different gastric volume have improvement of glucoseetabolism without serious complications, showing that the Roux-en-Y gastric bypass surgery isa stable lower blood sugar and relatively safe surgical treatment of T2DM.2.The Roux-en-Y gastric bypass surgery with different stomach volume have no hypoglycemicdifferences, indicate that there is no obvious connection between the stomach volume size andhypoglycemic effects.We speculated that the exclusion of the duodenum and proximal jejunumis closely related to improve glucose metabolism.3. The average daily food intake and body weight are affected by the size of the stomachvolume, and the Roux-en-Y gastrojejunostomy with stomach capacity maintenance(Duodeno-jejunal Bypass, DJB) is better for the treatment of non-obese type2diabetes.