The Effect Of The Change Of Ghrelin And Its Receptor On Accelerating Diabetic Encephalopathy By Blood Glucose Fluctuation In GK Rats

Objective:To explore the effect of the change of Ghrelin and its receptor(GHSR1α)on accelerating the diabetic encephalopathy by blood glucose fluctuation in rats.Method:Eight male Wistar rats as normal control group(N group),16 male GK rats were randomly divided into sustained hyperglycemia group(MS)and blood glucose fluctuation group(MF).MF group rats daily take the intraperitoneal injections of glucose and subcutaneous injections of insulin at different hours to cause the blood glucose fluctuation model,MS group rats daily take the intraperitoneal injections of glucose at different hours to cause the sustained hyperglycemia model,N group rats daily take the intraperitoneal injections of isodose NS,successive for 6 weeks.General symptoms of rats were daily observed.The behavioral detection in rats,including Morris water maze test,Y maze test and open-field experiment,were taken at the 6th week;The blood glucose at 9 time points in a day were tested at the end of the 6th week.All rats were taken anesthesia to death,beheaded in brain,isolation of hippocampus,the changes of pathological and neurons in rat hippocampus were observed by HE staining and toluidine blue staining.The expression of Ghrelin and GHSR1 α mRNA and protein in the hippocampus were detected by RT-PCR and Immunohistochemistry.Results:Compared with the N group,the speed of weight growth in MS and MF group rats slowed significantly,the cognitive function decreased significantly,the pathology changes and neuron changes in hippocampus were obviously serious,the expression of Ghrelin and GHSR1 α mRNA and protein in the hippocampus decreased significantly(P<0.05,P<0.01).Compared with MS group,MF group rats have more obviously changes in cognitive function,pathological changes in hippocampus,and the expression of Ghrelin and GHSR1α protein in hippocampus(P<0.05,P<0.01).Conclusion:The expression of Ghrelin and GHSR1α in hippocampal tissue of diabetic rats decreased significantly,playing an important role in accelerating the process of diabetic encephalopathy by blood glucose fluctuations.