酒精对NIT-1细胞葡萄糖激酶基因表达的影响

目的观察酒精对NIT-1细胞葡萄糖刺激后胰岛素分泌功能及葡萄糖激酶(Glucokinase)基因表达的影响。方法体外培养NIT-1细胞,使用不同浓度的酒精(0,50,100,200,400mmol／L)作用不同时间后(6,12．24h),用放射免疫法测定NIT-1细胞分泌胰岛素的量,用噻唑蓝(MTT)法检测NIT-1细胞代谢活性,用RT—PCR方法检测葡萄糖激酶基因mRNA的表达。结果酒精对NIT-1细胞代谢活性的抑制与酒精剂量和作用时间有关。酒精作用6h,NIT-1细胞葡萄糖刺激的胰岛素分泌增加;作用12,24h,葡萄糖刺激的胰岛素分泌降低。酒精作用6h．各剂量组葡萄糖激酶mRNA表达升高;酒精作用12,24h,各剂量组葡萄糖激酶mRNA表达均降低。结论酒精对NIT-1细胞葡萄糖刺激后胰岛素分泌及葡萄糖激酶mRNA表达的影响与作用时间、剂量有关。而葡萄糖激酶mRNA表达水平的改变可能是酒精影响NIT-1细胞胰岛素分泌的重要机制之一。

Effect of ethanol on glucokinase mRNA expression in NIT- 1 insulinoma cells

Objective To study the effects of ethanol on glucose-stimulated insulin secretion (GSIS) and glucokinase mRNA expression of NIT-1 insulinoma cells. Methods NIT-1 cells were exposed to various concentrations of ethanol(0,50,100,200,400?mmol/L)for various periods of time(6,12,24?h).The metabolic activity was judged by methyl thiazolyl tetrazolium(MTT)assay.The level of insulin secretion was measured by radioimmunoassay.Additonally,relative level of glucokinase mRNA expression was evaluated by RT-PCR method.Results The metabolic activity was inhibited in dose-and-time dependent manners.After exposed for 6?hours,ethanol increased the level of glucose-stimulated insulin secretion in the medium.After exposed for 12 and 24?hour,ethanol decreased the amount of glucose-stimulated insulin secretion in the medium.At 6?hour,ethanol upgraded glucokinase mRNA expression.At 12 and 24?hours,ethanol upgraded glucokinase mRNA expression.Conclusion Depending on the timing and concentrations,ethanol can exert both stimulatory and inhibitory effects on insulin secrection and glucokinase mRNA expression in NIT-1 cells.Influence of ethanol on glucokinase mRNA expression in NIT-1 cells maybe was one of the mechanisms involved in the effect of ethanol on insulin secretion.