酒精对小鼠NIT-1细胞胰岛素分泌及COXⅡ基因表达的影响

EFFECT OF ETHANOL ON INSULIN SECRETION AND COXⅡ mRNA EXPRESSION IN NIT-1 INSULINOMA CELLS

目的:观察酒精对小鼠NIT-1细胞胰岛素分泌功能的影响并初步探讨其机制。方法:体外培养的小鼠NIT-1细胞,经不同浓度酒精(0、50、100、200、400mmol/L)作用6、12、24h后,用放免法测定NIT-1细胞分泌胰岛素情况,半定量RT-PCR方法检测细胞色素氧化酶Ⅱ(cytochromeoxidaseⅡ,COXⅡ)基因mRNA的表达。结果:酒精作用6h,NIT-1细胞葡萄糖刺激的胰岛素分泌增加;作用12h、24h,葡萄糖刺激的胰岛素分泌降低。酒精作用6h,COXⅡmRNA表达升高,12h表达开始降低,24h时高浓度组表达呈显著性降低。结论:酒精可增加或降低NIT-1细胞胰岛素分泌,与酒精作用时间、浓度有关。酒精导致COXⅡmRNA表达水平的改变很可能是酒精影响NIT-1细胞胰岛素分泌的机制之一。

Objective： To study the effect and the mechanism of ethanol on insulin secretion of NIT-1 insulinoma cells. Method： NIT-1 cells were exposed to various concentrations of ethanol （0, 50, 100, 200, 400 mmol/L） for 6, 12 and 24 h. The level of insulin secretion was measured by radioimmunoassay. Meanwhile, COX Ⅱ mRNA expression was detected by RT-PCR method. Results： At 6h, ethanol increased the glucose-stimulated insulin secretion. At 12h and 24h, ethanol decreased the insulin secretion. COX Ⅱ mRNA expression was upgraded at 6 h and began to decrease at 12 h. At 24 h, high ethanol group decreased COX ⅡmRNA expression significantly. Conclusion- Depending on time and concentrations, ethanol can exert both stimulatory and inhibitory effects on insulin secretion and COX Ⅱ mRNA expression in NIT-1 cells. Influence of ethanol on COX Ⅱ mRNA expression in NIT-1 cells may be involved in the effect of ethanol on insulin secretion.