Effects Of Gastric Bypass On Blood Glucose In Diabetic Rats

Objective:Diabetes is one of the chronic disease which is harmful to our health. 85% of diabetes is of type 2 diabetes, there are more than 150 million patients suffering from type 2 diabetes in the world. And the morbidity rate has been increasing year by year. To all the middle-aged type 2 diabetic patients, their lives will be expected to decrease by 5-10 years. The chronic complication of diabetes is the significant reason for causing death and disability. Current major therapy in medical treatment, including alimentary control,physical training,oral antidiabetic drugs and insulin treatment. We expect these therapies can rigorously control patient's hyperglycemia so as to cut down the fatality rate and mutilation rate. But these ways can not cure diabetes in long-term, which need to be maintained through out the life and result in degression of quality of life. And because of bad dependence of patient, it is very hard to achieve the objective of controlling blood sugar rigorously.For the past few years, foreign scholars found that some weight reduction operation can cure diabetes and decrease its complications, especially the Gastric Bypass,which opened a new way for surgical therapy to diabetes.Gastric Bypass has the visible effect on blood glucose of diabetes patients. But, the exact mechanisms has not been known, and current report of curative effect are major on diabetes patients who have morbid obesity, to the patients who have no morbid obesity, the treatment still need long-term case observation and experiment. In this experiment, we make the focus point on observing diabetic rat's blood glucose,insulin level,glycosylated hemoglobin and shape of pancreas. Then comparing each and every preoperative index, postoperative index and observing the change. To aim at researching the effects of Gastric Bypass on blood glucose in diabetic rats and the influence to insulin and glycosylated hemoglobin in diabetic rats. Observing whether rat's weight and food-intake is related to the degression of blood glucose after Gastric Bypass.Methods: 24 male Wistar rats, healthy, weighted 200-300gm, induced by STZ were divided into 3 groups randomly: GBP group (O group); food restriction group (F group), restricting food-intake 12.5gm each rat everyday (about 1/3 food-intake of the inducted rat before operation, 4 weeks after operation, they can eat unrestricted. All the rats need not to be restricted drinking water); controls group (C group). 8 rats every group. Observed weight and average food-intake of every rat in the three groups. Determined the rat's blood glucose, insulin and glycosylated hemoglobin when they were empty stomach and 30 minutes after poured glucose. The rats of group O were absolute diet one day before operation,but drunk water unrestricted. One day after operation, let the rats have food. Observed the change of weight and average food-intake of the rats in each group; and determined the rat's blood glucose,insulin and glycosylated hemoglobin when they were empty stomach and 30 minutes after poured glucose on the first,second,third,forth and eighth week after operation. Twelve weeks after operation, executed the rats and took their pancreatic tissue for pathological examination, observed islet cells.Results:1 The value of fasting blood glucose: Compared to preoperative value, 1 week after operation, the value of fasting blood glucose of group O has decreased from 20.8±4.9mmol/L to 16.8±2.3mmol/L,(P<0.01); 2-8 weeks after operation the value of fasting blood glucose was reducing. 8 weeks after operation, the value of fasting blood glucose has decreased to 7.1±1.0mmol/L; And 2 weeks after operation, the value of fasting blood glucose of group F has decreased from 21.1±5.9mmol/L to 16.3±2.3mmol/L,(P<0.01); from 2 weeks after operation to the end, there was no significant difference in the value of fasting blood glucose(P>0.05). In group C, there was no significant difference in the value of fasting blood glucose at any time(P>0.05). 8 weeks after operation, there was significant difference in the value of fasting blood glucose in group O compared to group F and group C(P﹤0.01).2 The value of blood glucose when 30 minutes after poured glucose: Compared to preoperative value, 1 week after operation, the value of fasting blood glucose of group O has decreased from 30.2±3.1mmol/L to 25.4±6.0mmol/L,(P﹤0.01). 2-8 weeks after operation the value of blood glucose was reducing. 8 weeks after operation, the value of blood glucose has decreased to 10.7±3.2mmol/L(P﹤0.01); In group F and C, there were no significant difference in the value of blood glucose at any time(P>0.05). 8 weeks after operation, there was significant difference in the value of blood glucose in group O compared to group F and group C(P﹤0.01); there was no significant difference in the value of blood glucose in group F compared to group C(P>0.05).3 The value of fasting blood insulin: Compared to preoperative value, 1 week after operation, the value of fasting blood insulin of group O has increased from 27.9±3.4 IU/L to 32.0±3.5 IU/L,(P<0.01). 2-8 weeks after operation the value of blood insulin was increasing. 8 weeks after operation, the value of blood insulin has increased to 69.2±4.8 IU/L. In group F and group C, there was no significant difference in the value of blood insulin at any time(P>0.05). 8 weeks after operation, there was significant difference in the value of blood insulin in group O compared to group F and group C(P﹤0.01); there was no significant difference in the value of blood insulin in group F compared to group C(P>0.05).4 The value of blood insulin when 30 minutes after poured glucose: Compared to preoperative value, 2 weeks after operation, the value of blood insulin of group O has increased from 30.5±3.4 IU/L to 37.0±3.0 IU/L,(P<0.01). 2-8 weeks after operation the value of blood insulin was increasing. 8 weeks after operation, the value of blood insulin increased to 74.0±3.5 IU/L. In group F and group C, there was no significant difference in the value of blood insulin at any time(P>0.05). 8 weeks after operation, there was significant difference in the value of blood insulin in group O compared to group F and group C(P﹤0.01); there was no significant difference in the value of blood insulin in group F compared to group C(P>0.05).5 The blood glucose was negatively correlated with insulin of group O(P<0.01).6 There was no significant difference in the weight of group O; after operation the food-intake of group O is about three times the group F .7 After operation, pancreatic pathological section of group O showed that atrophy and retrogression change of islet cells were much ameliorative than that of pancreatic pathological section of group F and group C.Conclusion: This study shows that Gastric Bypass has visible therapeutically effect on blood glucose of diabetic rats. This effect has no association with weight loss and food-intake.