高脂诱导胰岛素抵抗大鼠糖代谢及血抵抗素、脂联素水平的变化

目的 探讨高脂饮食诱导的胰岛素抵抗大鼠糖代谢及抵抗素、脂联素水平的变化。方法 采用大鼠扩展胰岛素钳夹和3-^3H标记葡萄糖示踪技术，估计高脂诱导胰岛素抵抗（IR）大鼠肝糖及外周组织糖代谢的变化，同时采用酶免法检测血浆抵抗素及脂联素水平。结果 高脂喂养组（HF组）大鼠基础血浆游离脂肪酸（FFA）水平明显增高。钳夹稳态时，HF组血浆胰岛素水平明显高于N组，差异有统计学意义（P〈0．01），FFA也明显高于N组，差异有统计学意义（P〈0．01）。HF组葡萄糖输注率（GIR）较N组减少38％，胰岛素介导的葡萄糖利用率（GRd）较N组亦明显减少21％。N组大鼠肝糖输出（HGP）明显抑制达71％，而在HF组胰岛素介导的HGP的抑制作用受到明显障碍（仅抑制30％）。钳夹结束时，N组血浆抵抗素水平与基础值相比明显降低，差异有统计学意义（P〈0．05），而HF组明显高于N组（P〈0.05）。两组血浆脂联素水平在钳夹后均明显下降差异有统计学意义（P〈0.05）。结论 高脂饮食诱导大鼠产生了外周和肝脏的IR。IR的形成可能与血浆FFA升高和在高胰岛素状态下较高的血浆抵抗素水平有关。

Changes of glucose metabolism, plasma resistin and adiponectin levels in the insulin-resistant rats induced by high-fat diet

Objective To investigate the changes of glucose metabolism,plasma resistin and adiponectin levels in insulin-resistant rats induced by high-fat diet.Methods Changes of peripheral and hepatic glucose metabolism in awake rats were evaluated by hyperinsulinemic euglycemic clamp technique combined with 3-3H glucose as a tracer.And plasma resistin and adiponectin were detected by ELISA.Results In baseline,plasma free fatty acids(FFA) levels were increased in high-fat diet rats(HF) compared with normal chow diet rats(N).During clamp steady-state,plasma insulin and FFA levels were higher in HF group compared with control(P<0.01).In HF group,the glucose infusion rate(GIR) and glucose disappearance rate(GRd) were reduced by 38% and 21%,respectively.And the insulin-mediated suppression of hepatic glucose production was up to 71% in N group,but it was impaired and only up to 30% in HF rats(P<0.01).At the end of the clamp,plasma resistin levels were decreased in N group and lower than that in HF rats(P<0.05).Howevre,plasma adiponectin levels were both decreased after clamp(P<0.05).Conclusion High-fat diet induced peripheral and hepatic insulin resistance in rats.It might be associated with elevated FFA and higher plasma resistin levels during hyperinsulinemia.