Effects Of Rosiglitazone Natrium On The Expression Of IGF-1 In Pancreatic Islet Of Diabetic Rats

Objective:To explore the proliferation effect of Rosiglitazone natrium on survival pancreatic beta cell of rats with type 1 diabetes mellitus.Methods: Eight rats were randomly selected from sixty-eight male Sprague-Dawley rats for normal control group(group A),the left were administered with STZ intraperitoneally at a dose of 65mg/kg body weight and 72 hours later,fasting blood glucose(FBG)levels were determined,those with FBG≥16.7mmol/L were served as diabetes models,then the rats were randomly assigned as Rosiglitazone natrium treatment group(group B,n=24)and diabetes mellitus group(group C,n=24).Rosiglitazone natrium were applied via intragastric administration at a dose of 5mg/kg.d^-1in group B,while Sodium Chloride were applied at the same dose and method to group A and C.72 hours after the administration of STZ and 1-,2-,4-,7-and 10 weeks after the administration of Rosiglitazone natrium,4 rats were randomly selected and put to death in group B and C,and blood samples were collected for the assessment of FBG,insulin levels.Pancreas specimens were obtained and preserved in the same time.The morphologic changes were observed under light and electron microscopes.The method of immunohistochemisty was used to evaluate the expression levels of insulin and IGF-1 in pancreatic islet.Results:(1)In group B,the FBG levels decreased gradually,while the levels of FINS increased gradually.(2)In group B,the morphologic injuries of remnant islet were come to recovery,the size of survival islet were enlarged and the beta cell mass were raised,the amount of secretory granule in beta cells of pancreatic islet increased gradually.(3)The expression levels of INS and IGF-1 in islet were increased in group B and were significantly higher than that in group C.The levels of IGF-1 has a positive correlation with blood insulin levels(r=0.934,P＜0.01),and also has a positive correlation with the levels of INS expressing in the islets(r=0.982,P＜0.01).Conclusions:Rosiglitazone natrium has facilitative effect on beta cells proliferation and regeneration to some extent in experimental type 1 diabetic rats, perhaps via promoting survival islet to express IGF-1.