动物造模 z-bio 2021-12-07 750

　　OBJECTIVE: To observe the changes of insulin secretion in db/db mice pancreatic islets after blocking the expression of local angiotensin II type 1 receptor (AT1R) by RNA interference technology, and to explore its underlying mechanism.

　　Method: Isolate db/db and db/m mouse pancreatic islets, and detect AT1R mRNA and protein expression. Construction of NA interfering recombinant adenovirus targeting mouse AT1R gene (Ad-siAT1R) and recombinant adenovirus containing regulatory sequences (Ad-siControl). The isolated and cultured db/db mouse pancreatic islet cells were divided into three groups: Ad-siAT1R infection group, Ad-siControl infection group and blank control group. Pancreatic islet cells were cultured for 72 hours after adenovirus infection. The expression of AT1R, GLUT-2 and glucokinase (GCK) in each group was detected, and the islet perfusion system was used to detect dynamic insulin secretion.

　　Result: The expression level of AT1R mRNA and protein in db/db mouse pancreatic islets is about twice that of db/m mouse pancreatic islets (Pu003c0.05). After adenovirus infection, compared with the Ad-siControl group, the expression level of pancreatic islet AT1R mRNA in the Ad-siAT1R group decreased by 75% and the protein expression level decreased by 65%, while GLUT-2 and GCK were respectively 190% and increased by 121% Pu003c0.05 ). In the blank control group and the Ad-si control group, islet perfusion showed a significant decrease in the first stage of insulin secretion. This is only 1.8 times the baseline level, but the Ad-si AT1R group reached a peak of 140 mU/1-2 minutes. After high sugar load. L is 2.8 times the basal level, indicating that insulin secretion in the first stage has been significantly improved.

　　Conclusion: RNA interference can specifically block the local AT1R expression of pancreatic islets, up-regulate the expression of GLUT-2 and GCK, and restore phase 1 insulin secretion. This may be one of the mechanisms by which AT1R blockers improve.