Losartan improves human islet ?-cell function damaged by angiotensin Ⅱ
- VernacularTitle:血管紧张素Ⅱ对人胰岛B细胞分泌功能的影响及氯沙坦的保护作用
- Author:
Min LIU
;
Dehong CAI
;
Hua ZHANG
- Publication Type:Journal Article
- Keywords:
Angiotensin Ⅱ;
human islet;
Ca~(2+);
CaM
- From:
Chinese Journal of Practical Internal Medicine
2006;0(23):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective This study aimed to investigate the effects of angiotensin Ⅱ and Losartan pretreatment on regulating insulin secretion in human islet ? cells.Methods We measured changes in intracellular calcium by confocal laser scanning microscopy using Flou3-AM-loaded human islet cells.RT-PCR was used to measure changes in intracellular CaM.Dynamic insulin secretory responses were determined by chemiluminescence following perfusion of human islets.Results Exposure of the isolated islets to angiotensin Ⅱ induced glucose-stimulated insulin release coupled with intracellular calcium ascending in first phase and descending in second phase.Intracellular CaM concentration could not be affected by angiotensin Ⅱ.Conclusion The change of free Ca2+is induced by the combination of AngⅡ with ATI receptors of islet B cells,which results in the damage to islet B cells.Losartan pretreatment protects the islet B-cell function by inhibiting calcium overload.