【作者】 李梅；

【导师】 易玮；

【作者基本信息】 广州中医药大学 ， 针灸推拿学， 2011， 硕士

【摘要】 研究目的本研究是导师课题的一部分,主要观察针刺对胰岛素抵抗模型大鼠骨骼肌IRS-1、IRS-2、GLUT4的mRNA和蛋白表达的影响,从分子水平探讨针刺调整胰岛素抵抗的机理。研究方法将24只雄性SD大鼠(180-220g)按体重随机分为3组,每组8只,分别为空白组、模型组和针刺组。空白组予普通饲料喂养,其余各组予高糖高脂高盐饲料喂养。从第6周开始,每隔1周对空白组和模型组大鼠从眼眶静脉窦采血1次,检测空腹血糖(FPG)、血浆胰岛素(FINS),并计算胰岛素敏感性指数(ISI),当模型组大鼠ISI较空白组显著降低(P<0.01)为造模成功。第12周造模成功后,空白组继续予普通饲料喂养3周,模型组继续予高脂高糖高盐饲料喂养3周,针刺组继续予高脂高糖高盐饲料喂养3周,同时针刺组给予电针治疗日1次,取内关、足三里、三阴交和肾俞穴。治疗结束后各组大鼠禁食12小时过夜,次晨行眼眶静脉窦采血,检测FPG、FINS、C肽等指标,FPG测定采用葡萄糖氧化酶法,FINS、C肽测定采用ELISA法,ISI用1/(CFPG X JFINS)公式计算；胰岛素灌注后将大鼠处死,取股四头肌,用RT-PCR、Western blotting等检测手段,观察针刺前后胰岛素抵抗模型大鼠骨骼肌IRS-1、IRS-2、GLUT4的mRNA和蛋白表达情况。结果予高脂高糖高盐饲料喂养12周后,模型组大鼠和针刺组大鼠的FPG、FINS与空白组相比均显著升高(P<0.01), ISI显著下降(P<0.01),提示造模成功。经过3周针刺治疗后,针刺组的FPG、FINS、C肽与模型组比较显著降低(P<0.01, P<0.05), ISI与模型组相比显著升高(P<0.01)。模型组大鼠骨骼肌IRS-1 mRNA表达较空白组显著降低(P<0.01)；针刺组大鼠骨骼肌IRS-1 mRNA较模型组显著升高(P<0.01)。模型组大鼠骨骼肌IRS-2 mRNA表达较空白组显著降低(P<0.01), IRS-2蛋白表达与空白组相比无明显变化(P>0.05)；针刺组大鼠骨骼肌IRS-2 mRNA和IRS-2蛋白表达均较模型组显著升高(P<0.01)。模型组大鼠骨骼肌GLUT4 mRNA和GLUT4蛋白表达均较空白组显著降低(P<0.01)；针刺组大鼠骨骼肌GLUT4 mRNA和GLUT4蛋白表达均较模型组显著升高(P<0.01)。结论研究结果提示,针刺改善胰岛素抵抗主要是通过调节PI3K通路的信号转导来实现,其机理与增加IRS-1、IRS-2、GLUT4 mRNA表达和GLUT4蛋白表达有关。更多还原

【Abstract】 ObjectiveOur aim was to observe the effects of acupuncture on IRS-1, IRS-2 and GLUT4 of insulin resistance model rats’ femoris muscle, so as to further explore its underlying mechanism.MethodsTwenty four male SD rats were divided randomly into three groups:the blank group, the model group and the acupuncture group. We induced insulin resistance model through the high glucose, high salt and high fat diet. From the sixth week, we tested FPG and FINS in the rat’s blood every week, then figured out the ISI. When the ISI of the model group and the blank group was statistically significant (P< 0.01), the model was success. Then in the next three weeks, the rats of the blank group were fed by normal diet, while the rats of the model group and the acupuncture group were fed by the high glucose, high salt and high fat diet. The rats of the acupuncture group were treated by electroacupuncture at the same time, twenty minutes per day. We chose four points:Neiguan, Zusanli, Sanyinjiao and Shenshu.After three weeks of treatment, all rats were drew blood, preparing for testing FPG, FINS and C-P. Then they were perfused by insulin before being killed. Their quadriceps femoris muscle was cut off. Finally IRS-1, IRS-2 and GLUT4 were tested by methods such as RT-PCR, western blotting and so on.ResultsInsulin resistance rat model was built successfully. FPG and FINS of the model group rose evidently(P<0.01), ISI of the model group declined remarkably(P<0.01). After treatment, FPG, FINS, ISI and C-P of the acupuncture group improved evidently(P<0.01, P＜0.05). IRS-1 mRNA of the model group declined remarkably (P<0.01). IRS-1 mRNA of the acupuncture group rose evidently (P＜0.01).IRS-2 mRNA of the model group declined remarkably (P＜0.01). IRS-2 mRNA and IRS-2 protein expression of the acupuncture group rose evidently (P＜0.01). GLUT4 mRNA and GLUT4 protein expression of the model group declined remarkably (P<0.01). GLUT4 mRNA and GLUT4 protein expression of the acupuncture group rose evidently (P＜0.01).GonelusionIn this study, we found acupuncture’s regulating action to PI3K route. We presume acupuncture treat insulin resistance model rats through increasing IRS-1 mRNA, IRS-2 mRNA and protein expression, GLUT4 mRNA and protein expression. The action mode and pathway of these protein were not clear yet, which need us to study further.更多还原