Yasuda K, Kitabchi A E
Diabetes. 1980 Oct;29(10):811-4. doi: 10.2337/diacare.20.10.811.
We have investigated changes in insulin binding in erythrocytes in response to overnight ingestion of 1 mg dexamethasone or 10 mg of prednisone in two groups of eight lean, healthy subjects. Dexamethasone administration reduced insulin binding from 9.6 to 6.8% (P < 0.001) with concomitant increase in basal plasma insulin from 10.5 to 14.1 microU/ml (P < 0.05). Prednisone ingestion reduced insulin binding from 9.9 to 7.9% (P < 0.01), but the increase in basal insulin from 16.9 to 20.6 microU/ml was not significantly different. The decrease in insulin binding with both dexamethasone and prednisone was associated with decreased affinity of erythrocyte for insulin at low occupancy and the increase in the dose of unlabeled insulin resulted in 50% inhibition of specific binding without changes in the number of receptors. The earliest decrease in insulin binding was noted within 2 h after ingestion of 1 mg of dexamethasone. These data suggest that acute alteration of insulin receptor function could occur in erythrocytes by small amounts of dexamethasone or prednisone through a mechanism consistent with a decrease in receptor affinity rather than a decrease in the number of receptors.
我们在两组各八名健康瘦体型受试者中，研究了过夜服用1毫克地塞米松或10毫克泼尼松后红细胞中胰岛素结合情况的变化。服用地塞米松后，胰岛素结合率从9.6%降至6.8%（P<0.001），同时基础血浆胰岛素从10.5微单位/毫升升至14.1微单位/毫升（P<0.05）。服用泼尼松后，胰岛素结合率从9.9%降至7.9%（P<0.01），但基础胰岛素从16.9微单位/毫升升至20.6微单位/毫升，差异无统计学意义。地塞米松和泼尼松导致的胰岛素结合率下降，与红细胞在低占有率时对胰岛素的亲和力降低有关，未标记胰岛素剂量增加导致特异性结合被50%抑制，而受体数量无变化。服用1毫克地塞米松后最早在2小时内就观察到胰岛素结合率下降。这些数据表明，少量地塞米松或泼尼松可通过与受体亲和力降低而非受体数量减少相一致的机制，使红细胞中的胰岛素受体功能发生急性改变。
