Preparation And Evaluation Of Normal Weight Insulin Resistance Rat Model

Objective: Male Sprague-Dawley (SD) rats were fed with high-sucrose diet to make normal weight insulin resistance rat model.We evaluated the effects of high-sucrose diet on rats's Insulin Resistance (IR) and investigated the possible pathophysiolgical mechanisms of IR development in the model.Methods: 30 male SD rats were randomly assigned into two groups: normal control group(NC group, n=15) fed with normal diets; experimental groups were high-sucrose group (HS group, n=15) fed with high-sucrose diet, offered rats with different diets to correspond group respectively. The body weight was measured at the right time. 16 weeks after intervention,an intraperitoneal glucose tolerance test (IPGTT) was made. 20 weeks after intervention, the blood sample was taken to measure fasting plasma glucose (FBG), total cholesterol (TC), triglyceride (TG),high density lipoproteins cholesterol (HDL-c),free fatty acids( FFA), and fasting serum insulin (FINS). Hyperinsulinemic-euglycemic clamp combined with intravenous infusion of 3-~3H glucose technique was administered to each animals to evaluate the insulin sensitivity of the rats. We measured the weight of visceral fat,used Hematoxylin and Eosin(HE) staining to observe the liver, skeletal muscle,and the thoracic arteriae aorta pathomorphology under light microscope. Sudan red staining was used to observe the liver under light microscope. Electron microscope was used to observe the liver, skeletal muscle,and the thoracic arteriae aorta pathomorphology.Result: The rat weight changes were not different between the two groups. 2h plasma glucose levels were significantly higher during IPGTT in HS group, but FBG was not different between the two group.Serum TG was higher in HS group than that in NC group.but TC was not different between the two groups.Serum HDL-c level in HS group was significantly lower than that in NC group, but serum FFA level was not different...