Watanabe N, Kobayashi M, Maegawa H, Ishibashi O, Takata Y, Shigeta Y
Endocrinol Jpn. 1985 Dec;32(6):829-36. doi: 10.1507/endocrj1954.32.829.
We studied the in vivo and in vitro effect of p-chlorophenoxyisobutyrate (CPIB) on insulin binding and glucose transport in isolated rat adipocytes. In the in vitro study, adipocytes were incubated with 1mM of CPIB for 2 h at 37 degrees C, pH 7.4, and then insulin binding (37 degrees C, 60 min) and 3-0-methylglucose transport (37 degrees C, 2s) were measured. Incubation with CPIB did not affect either insulin binding or glucose transport in the cells. The addition of insulin (10 ng/ml) with CPIB to the incubation media also did not affect the following insulin binding and glucose transport. In the in vivo study, rats were fed a high sucrose-diet containing 0.25% CPIB for 7 days. Serum cholesterol, plasma free fatty acid, and insulin levels were significantly decreased in the CPIB-treated rats. The treated rats demonstrated an almost 2 fold increased maximal binding capacity for insulin (189,000 sites/cell for treated vs 123,000 sites/cell for control cells). Basal glucose transport (glucose transport in the absence of insulin) significantly decreased in the CPIB-treated rats, although insulin-stimulated glucose transport was comparable in treated and control cells. Thus, CPIB might have no direct effect on glucose transport and insulin binding, as determined by the in vitro studies. Furthermore, a relatively short-term in vivo treatment with CPIB, such as 7 days, did not stimulate glucose transport.
我们研究了对氯苯氧异丁酸（CPIB）对分离的大鼠脂肪细胞中胰岛素结合和葡萄糖转运的体内和体外作用。在体外研究中，将脂肪细胞与1mM的CPIB在37℃、pH 7.4条件下孵育2小时，然后测量胰岛素结合（37℃，60分钟）和3-0-甲基葡萄糖转运（37℃，2秒）。用CPIB孵育对细胞中的胰岛素结合或葡萄糖转运均无影响。在孵育培养基中添加胰岛素（10 ng/ml）和CPIB也不影响随后的胰岛素结合和葡萄糖转运。在体内研究中，给大鼠喂食含0.25% CPIB的高蔗糖饮食7天。经CPIB处理的大鼠血清胆固醇、血浆游离脂肪酸和胰岛素水平显著降低。处理后的大鼠对胰岛素的最大结合能力几乎增加了2倍（处理组为189,000个位点/细胞，对照组为123,000个位点/细胞）。尽管经胰岛素刺激的葡萄糖转运在处理组和对照组细胞中相当，但经CPIB处理的大鼠基础葡萄糖转运（无胰岛素时的葡萄糖转运）显著降低。因此，如体外研究所确定的，CPIB可能对葡萄糖转运和胰岛素结合没有直接影响。此外，用CPIB进行相对短期的体内处理，如7天，并未刺激葡萄糖转运。
