Effect of angiotensin II on insulin secretion function of RIN-m cell and its mechanism
10.3760/cma.j.issn.1000-6699.2010.03.014
- VernacularTitle:血管紧张素Ⅱ对RIN-m细胞胰岛素分泌功能的影响及机制探讨
- Author:
Xin LU
;
Hua ZHANG
;
Jun Lü
;
Hong CHEN
;
Dehong CAI
- Publication Type:Journal Article
- Keywords:
Angiotensin Ⅱ;
β-cell;
Uncoupling protein 2;
Mitochondron;
Insulin secretion
- From:
Chinese Journal of Endocrinology and Metabolism
2010;26(3):221-224
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of angiotenisn ⅡI (Ang Ⅱ) on RIN-m β-cell,and to explore the mechanism of β-cell function impairment caused by Ang Ⅱ.Methods RIN-m cells were cultured with various concentrations of AngⅡ (0.1,1,10,100 nmol/L).After incubation for 24 hours,the basal(3.3 mmol/L) and glucose-stimulated(16.7 mmol/L) insulin secretion(GSIS)were detected by radioimmunoassay,mRNA and protein expressions of uncoupling protein 2(UCP2)were determined by RT-PCR and Western blot,respectively.The intracellular ATP content was measured by luciferase bioluminescence.The mitochondrial membrane potential and cellular Ca~(2+) concentration were detected by flow cytometry.Results (1) Various concentrations of Ang Ⅱ had no significant influence on the basal insulin secrection of RIN-m cell(F=0.644,P = 0.634).Except for 0.1 nmol/L AngⅡ,the other concentrations of Ang Ⅱ markedly reduced GSIS of RIN-m cells(F= 118.528,P = 0.000).(2) Compared with the control group,Ang Ⅱ significantly increased mRNA and protein expression of UCP2(F= 1 370,P = 0.000;F=675.175,P = 0.000).(3)Except for 0.1 nmol/L Ang Ⅱ,the other concentrations of Ang Ⅱ significantly decreased the mitochondrial membrane potential,cellular ATP content,and cellular Ca2+ concentration of RIN-m cell(F=4.035,P=0.008;F=3.353,P = 0.013;F=5.867,P = 0.001).Conclusion Ang Ⅱ impairs GSIS of p-cell,the mechanism of impairment may be interpreted that Ang Ⅱ can increase the expression of UCP2,furthermore,it can reduce mitochondrial membrane potential,decrease the content of cellular ATP and the concentration of cellular Ca~(2+),can finally impair the function of β-cell.