摘要
目的 探讨糖皮质激素对原代培养老鼠脂肪细胞的糖转运活动及胰岛素信号肽的影响。方法 分离的老鼠脂肪细胞在 5mmol浓度葡萄糖加地塞米松 0 3μmol分别孵育 2h、8h、16h和 2 4h ,然后测定糖的转运活动 ;用Westernblotting测定细胞内胰岛素受体底物 (IRS) 1/ 2、肌醇磷脂 - 3-激酶 85亚单位 (p85 )和蛋白激酶B(PKB)的蛋白表达。结果 地塞米松治疗抑制了基础的和胰岛素刺激的葡萄糖转运活动 ,产生最大抑制作用时间分别为 2h和 2 4h ,对IRS1的蛋白表达的抑制作用与培养的时间长短成正比。同时 ,它也削弱了p85和PKB的蛋白表达 ;但对IRS2呈现上调作用。结论 糖皮质激素可以抑制葡萄糖的转运活动 ,诱导胰岛素抵抗。
Objective To explore the effect of glucocorticoid on glucose transport activity and the expression of insulin signaling peptides in the primary cultured rat adipocytes .Methods Isolated rat adipocytes were cultured for 2h,8h,16h and 24h respectively at 5 mmol glucose with dexamethasone (Dex) 0 3μmol. Then the glucose uptake, cellular contents of insulin receptor substrate (IRS) 1/2, phosphatidylinositol 3-kinase 85 subunit (p85) and protein kinase B(PKB)were measured by Western blotting.Results These adipocytes treated with Dex have shown to impair the basal and insulin-induced glucose uptake with a maximum inhibition at 2h and 24h respectively; Dex down-regulated IRS1 protein expression in a time-dependent manner and up-regulated IRS2 content. The cellular p85 and PKB contents were also decreased by Dex. Conclusion Chronic exposure to glucocorticoid can inhibit glucose uptake and induce insulin resistance. The mechanism may be involved in affecting the expression of insulin signaling peptides.
出处
《中国医师杂志》
CAS
2001年第9期576-578,共3页
Journal of Chinese Physician
