胰岛素、体重指数、磺脲类药对2型糖尿病脂肪细胞胰岛素受体的影响

Influence of insulin,obesity and sulfonylureas on adipocyte insulin reaptor in type 2 diabetes mellitus

目的 研究 2型糖尿病 (DM)脂肪细胞胰岛素受体 (ICIR)的改变以及胰岛素、肥胖、磺脲类药对其的影响。方法 Rodbell法获取游离脂肪细胞 ,FantusIG’s法行脂肪组织体外孵育实验 ,放射受体分析法分别测肥胖 2型DM非肥胖2型DM、单纯肥胖及正常对照组的ICIR。结果 (1)各研究组ICIR数量较对照组明显减低 ,两 2型DM组之间ICIR减少无明显差异。 (2 )两 2型DM组低亲和力高容量受体及高亲和力低容量受体均明显减少 ,但以低亲和力高容量受体的减少更甚 ,Ins与ICIR亲和力减低。单纯肥胖组 2种受体均减少 ,亲和力无改变。 (3)体外实验结果显示 :经Ins孵育后ICIR数量减低 ,优降糖孵育后ICIR数量提高。结论 (1) 2型DMICIR存在数量减少及质的改变在 2型DM发病中起重要作用 ,肥胖对 2型DMICIR的改变无影响。 (2 )高胰岛素血症是导致ICIR减少的原因之一。 (3)磺脲类药物优降糖可改善 2型DMICIR的减少。

Objective To investigate the effect of insulin,obesity and sulfonylureas on adipocyte insulin receptor in type 2 diabetes mellitus (DM).Methods Isolated adipocytes were obtained by Rodbell's method.Adipose tissue incubation was done by Fantus's method.Radioreceptor assay was used to determine adipose insulin receptor in type 2 DM group with obesity,type 2 DM group withont obesity,primary obesity group and control group.Results (1) The adipocyte insulin receptor decreased in number significantly in groups of type 2 DM,with and withont obesity and of primary obesity,compared with control group.The adipocyte insulin receptor in both type 2 DM groups decreased significantly more than that in primary obesity group.There is no statistical difference between type 2 DM with and without obesity.(2)In both type 2 DM groups the receptors with low affinity and high affinity were reduced and insulin receptor affinity was lowered.The affinity in the primary obesity group did not change,but both kinds of receptors decreased.(3)Increase insulin level was an inverse relationship with the reduced insulin receptor number in vivo and in vitro.Conclusions (1)The change of affinity and the decrease of insulin receptors was one of important causes of type 2 DM,obsity played a minor role in type 2 DM.(2)Heperinsulinemia was one of influencing factors for reduction of adipocyte insulin receptors of type 2 DM.