长期酒精摄入对大鼠胰岛素分泌功能的影响

EFFECT OF CHRONIC ETHANOL INTAKE ON INSULIN mRNA EXPRESSION IN RATS

目的:研究长期酒精摄入对大鼠血糖、血清胰岛素及胰岛素基因表达影响。方法:清洁级Wistar大鼠80只,雌雄各半,随机分为对照组和低、中、高剂量组,摄入酒精剂量分别为0、0.8、1.6和2.4g/(kgbw?d)。给予酒精18w后,进行口服葡萄糖耐量试验(OGTT),第19w末,断头处死,测定空腹血糖和血胰岛素水平,计算Homa-β功能指数(HBCI)。提取胰腺总RNA,半定量RT-PCR测定胰岛素mRNA表达水平。结果:雌性大鼠高剂量组空腹血糖升高、空腹血清胰岛素下降,中、高剂量组HBCI及胰岛素基因表达均降低;雄性大鼠OGTT高剂量组0和1.5h血糖升高,空腹血糖高剂量组升高,低、中剂量组空腹血胰岛素升高,随着剂量增加,HBCI及胰岛素基因表达先升高后降低。结论:长期高剂量酒精摄入可导致胰岛素mRNA基因表达改变,胰岛β细胞功能受损。

Objective： To study the effect of chronic ethanol intake on plasma glucose, plasma insulin and pancreas insulin mRNA expression in rats. Method： Rats were divided into control （C）, low （L）, moderate （M） and high （H） alcohol groups. Each group had ten males and ten females. Alcohol was administered at 0, 0.8, 1.6 and 2.4 g/ （kg bwod） respectively and given to rats by gavage. Oral glucose tolerance test was performed after 18 w treatment. In the nineteenth week, serum was collected for determination of fasting plasma glucose and insulin. Homa beta cell function index （HBCI） was calculated. The insulin mRNA expression in pancreas was detected by RT-PCR. Results： In female rats, the fasting plasma glucose was higher and fasting plasma insulin was lower in H group than C group. HBCI and insulin mRNA expression were lower in M and H groups than C group. In male rats, OGTT results showed the glucose concentrations at Oh and 1.5h were higher in H group than C group. The fasting plasma glucose in H group and fasting plasma insulin in L and M groups were higher than in C group. With increasing ethanol doses, HBCI and insulin mRNA expression increased first, then decreased. Conclusion： Chronic high dose ethanol intake could change insulin mRNA expression and damage the function of pancreatic islet β cells.