【摘要】 目的：观察G蛋白家族中G11α和GqαmRNA在乙醇诱导下对大鼠骨骼肌胰岛素抵抗的作用。 方法：①实验于2003-09／2005-03在山东省立医院中心实验室完成。选用雄性Wistar健康成年大鼠40只。随机将大鼠分为4组，对照组、大剂量饮酒组、中剂量饮酒组、小剂量饮酒组，每组10只。对照组：胃管灌注蒸馏水5．0g／(kg·d)，1次／d；大、中、小剂量饮酒组：胃管灌注乙醇量5．0，2．5，0．5g／(kg·d)，1次／d，每组均喂养5个月。②采用强生血糖仪测定空腹血糖和糖负荷后2h血糖。③采用液体闪烁计数仪分别测量基础状态下、胰岛素刺激后的组织非特异吸收的2-D-~3H葡萄糖量。基础状态葡萄糖摄取=单位重量基础状态肌肉计数-单位重量煮沸变性肌肉计数；胰岛素刺激后葡萄糖摄取=单位重量胰岛素刺激后肌肉计数-单位重量基础状态肌肉计数。④采用反转录聚合酶链反应法测定G11α和Gqα mRNA水平。采用蛋白质印迹实验测定G11α和Gqα蛋白水平。⑤各组间比较采用单因素方差分析。 结果：大鼠40只均进入结果分析。①各饮酒组大鼠空腹血糖和糖负荷后2h血糖与对照组相近。②大、中剂量饮酒组大鼠基础状态骨骼肌糖摄取量与对照组比较，分别下降29％，72％(P<0．05)；胰岛素刺激后，分别下降27％，61％(P<0．05)；小剂量饮酒组大鼠无明显变化。③大、中、小剂量饮酒组大鼠骨骼肌G11α mRNA表达与对照组比较，分别下降57％，42％，38％(P<0．05-0．01)；Cqα mRNA表达无明显变化。④大鼠长期摄入乙醇后骨骼肌G11α和Gqα蛋白水平变化与mRNA水平变化趋势一致。 结论：①乙醇喂养5个月后，大鼠机体水平上没有表现出明显的糖代谢紊乱。②摄入乙醇剂量为5．0g／(kg·d)和2．5g／(kg·d)5个月后，大鼠骨骼肌产生明显的胰岛素抵抗。③长期摄入乙醇可影响大鼠骨骼肌G11α表达，并呈剂量依赖性。④各饮酒组大鼠骨骼肌Gqα mRNA表达及其蛋白水平变化不明显。更多还原

【Abstract】 AIM:To observe the resistive effects of G11α and Gqα mRNA of G protein family on insulin in skeletal muscle in rats under the induction of ethanol. METHODS:① The experiment was conducted at the Central Laboratory, Shandong Provincial Hospital from September 2003 to March 2005. Forty adult Wistar healthy male rats were selected, and were divided randomly into 4 groups:control group, large dose group, middle dose group and small dose group with 10 rats in each group. Control group:the rats were filled with 5.0 g/kg distilled water per day with gastric canal, once a day; Large, middle and small dose group:The rats were filled with 5.0,2.5,0.5 g/kg per day ethanol with canal of stomach, once a day, for 5 months in every group. ② The levels of fasting plasma glucose and plasma glucose of glucose load 2 hours were measured with LIFESCAN glucose meter. ③ The dosage of insulin-stimulated glucose 2-D-~3H were measured under basic status with Liquid Scintillation Counters; Glucose intake under basic status=muscle counting of unit weight under basic status-boiling degeneration muscle counting of unit weight; Glucose intake after insulin stimulation=muscle counting of unit weight after insulin stimulationmuscle counting of unit weight under basic status. ④ The levels of G11α and Gqα mRNA were detected with reverse transcription polymerase chain reaction. The levels of G11α and Gqα protein were tested with Western blot. ⑤ The comparison among groups was done with single factor analysis of variance. RESULTS:Forty rats were all involved in the result analysis. ① The levels of fasting plasma glucose and plasma glucose of glucose load 2 hours in every drinking group were similar to those in control group. ② The dosage of glucose intake in skeletal muscle under basic status in rats of large and middle dosage drinking group decreased 29%,72%(P<0.05), respectively, as compared with that in the control group; After insulin stimulation, decreased 27%,61%(P<0.05), respectively; There were insignificant changes in rats of small dose drinking group. ③ The Gl la mRNA expression in skeletal muscle in large, middle and small dose drinking group decreased 57%,42%,38%(P<0.05-0.01), respectively, as compared with that in the control group. There were insignificant changes in Gqα mRNA expression. ④ The changes of G11α and Gqα protein were the same to mRNA changes in skeletal muscle after ethanol intake for a long time. CONCLUSION:① After feeding with ethanol for 5 months, there is insignificant glycometabolism derangement appeared in rat body level.② Insulin resistance occurs in skeletal muscle in rats apparently after intaking ethanol at the dosage of 5.0 g/kg per day and 2.5 g/kg per day for 5 months. ③ Long term of ethanol intake may have effects on G11 α expression in skeletal muscle in rats, and shows dose-dependent effect. ④ The changes of Gq α mRNA expression and its protein level in skeletal muscle in rats of every drinking group are insignificant.更多还原