Bertoli A, Caputo S, Marini M A, Santini S A, Ghirlanda G, Greco A V
Istituto di Clinica Medica, Università Cattolica SC, Roma, Italia.
Horm Res. 1989;31(5-6):238-43. doi: 10.1159/000181124.
Insulin resistance has been demonstrated both in insulin deficiency and insulin excess in man and in animals. This study was carried out in normal man to evaluate the role of insulinopenia in the pathogenesis of insulin resistance. Insulin suppression was obtained by 4 h somatostatin (SRIF) infusion. Insulin receptors on circulating monocytes were evaluated before and after SRIF infusion; an insulin tolerance test (ITT) was performed after SRIF, saline or SRIF and replacing basal insulin secretion. Insulin binding to circulating monocytes did not change after 4 h insulinopenia (2.19 +/- 0.30 vs. 2.35 +/- 0.80%), while insulin sensitivity appeared decreased after SRIF (KITT = 0.97 +/- 0.13) as compared with saline (KITT = 3.30 +/- 0.42), and this effect was prevented by insulin (KITT = 2.46 +/- 0.38). A relationship was detected between KITT and plasma insulin concentration before ITT (r = 0.85, p less than 0.01), suggesting that insulin deficiency is the main cause of the phenomenon observed. The present data suggest that basal insulin concentration plays an essential role in the control of insulin sensitivity. If insulin binding on monocytes mimics the behavior of major insulin target tissues, it is possible that the impaired insulin action after 4 h of insulin deficiency is related to a post binding effect.
胰岛素抵抗在人和动物的胰岛素缺乏及胰岛素过量状态下均有表现。本研究在正常人体中开展，以评估胰岛素缺乏在胰岛素抵抗发病机制中的作用。通过输注生长抑素（SRIF）4小时来实现胰岛素抑制。在输注SRIF前后评估循环单核细胞上的胰岛素受体；在输注SRIF、生理盐水后，或输注SRIF并补充基础胰岛素分泌后进行胰岛素耐量试验（ITT）。胰岛素缺乏4小时后，胰岛素与循环单核细胞的结合未发生变化（2.19±0.30对2.35±0.80%），而与生理盐水组（KITT = 3.30±0.42）相比，输注SRIF后胰岛素敏感性似乎降低（KITT = 0.97±0.13），且胰岛素可预防这种效应（KITT = 2.46±0.38）。在ITT前检测到KITT与血浆胰岛素浓度之间存在相关性（r = 0.85，p<0.01），提示胰岛素缺乏是观察到的该现象的主要原因。目前的数据表明基础胰岛素浓度在胰岛素敏感性的控制中起重要作用。如果单核细胞上的胰岛素结合模拟主要胰岛素靶组织的行为，那么胰岛素缺乏4小时后胰岛素作用受损可能与结合后效应有关。
