【摘要】 目的探讨胰岛素的长期作用对人脂肪细胞脂代谢的影响。方法　检测不同浓度胰岛素作用24h后脂肪细胞甘油释放率的基础值和刺激值,并使用RT-PCR检测脂肪分解的关键酶激素敏感性脂酶(HSL)和肿瘤坏死因子-α(TNF-α)的表达。结果胰岛素的长期作用可增加脂肪细胞的甘油释放率,并呈剂量效应和时间效应,100、500、1000nmol/L的胰岛素可使甘油释放率的基础值和刺激值分别增加17%～147%和28%～241%(P<0.01)。胰岛素的长期作用对脂肪细胞的HSLmRNA表达无影响,TNF-αmRNA的表达明显增加。结论在体外胰岛素的长期作用与其短期作用有所不同,可增加脂肪细胞的脂肪分解,具脂肪分解作用的TNF-α表达增加可能发挥了一定的作用。更多还原

【Abstract】 Objective Adipose tissue lipolysis plays an essential role in total body fuel metabolism. Our study is to assess the long- term effects of insulin on lipolysis in the human adipocytes. Methods The human adipocytes lipolytic rate was determined by glycerol release after the cells were exposed to insulin for up to 24 h. mRNA expression of hormone-senstive lipase (HSL) and tumor necrosis factor (TNF-α) were then assessed by RT-PCR. Results 100-1000 nmol/L insulin increased and stimulated the basal and stimulated glycerol release by 17%-147% and 28%-241% ( P < 0. 01) in a dose-dependent manner. Glycerol release in responded to insulin progressively with time. 500 nmol/L insulin increased TNF-α mRNA expression, but it had no effect on LPL mRNA expression. Conclusion Contradictory to its short-time anti- lipolytic effect, the long-term effect of insulin significantly stimulates lipolysis in human adipocytes. The increase can not be explained by changes in HSL, but maybe related in part with increased TNF-α.更多还原