The inhibitory effect of ghrelin on insulin release of mouse islet ?-cell line and its mechanism
- VernacularTitle:Ghrelin抑制胰岛?细胞胰岛素释放的机制探讨
- Author:
Lin LI
;
Yonghua WU
;
Tianpei HONG
- Publication Type:Journal Article
- Keywords:
Ghrelin;
Islet ?-cells;
Insulin
- From:
Chinese Journal of Diabetes
2000;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect of ghrelin on insulin release of mouse pancreatic islet ?-cell line(NIT-1 cells) and its probable mechanism.Methods NIT-1 cells were incubated in high-glucose DMEM with ghrelin.Then,the media was sampled for the assay of insulin by RIA.The(mRNA) expressions of glucose transporter 2(GluT2),pancreatic-duodenal homeobox-1(PDX-1),inwardly rectifying potassium channel with two transmembrane regions(Kir6.2) and sulphonylurea receptor 1(SUR-1) in the cells were detected by using RT-PCR.The cell proliferation was determined by MTT assay.Results(1) 10~(-9)mol/L to 10~(-7)mol/L of ghrelin inhibited dose-dependently the high-glucose challenged insulin release of the NIT-1 cells.(2) The mRNA expression of Kir6.2,but not GluT2,PDX-1and SUR-1,was down-regulated by 10~(-7)mol/L of ghrelin.(3) Ghrelin had no effect on proliferation of the cells.Conclusions Ghrelin inhibits high-glucose induced insulin secretion of the islet ?-cells.This effect may be secondary to the down-regulation for the expression of Kir6.2,(a component) of ATP-sensitive potassium channel.
