Bassas L, Zelenka P S, Serrano J, de Pablo F
Exp Cell Res. 1987 Feb;168(2):561-6. doi: 10.1016/0014-4827(87)90029-2.
We have previously reported that insulin-like growth factor (IGF) receptors appear to predominate over insulin receptors in early stages of embryogenesis in the chick (days 2-3 whole embryo membranes). Overall, [125I]IGF I and II binding to specific receptors was maximal when the rate of brain growth is highest. In the present study we used the embryonic chick lens, a well-defined tissue composed of a single type of cell, to analyse whether changes of insulin and IGF I binding are correlated with changes in growth rate and differentiation state of the cells. We show that both insulin receptors and IGF receptors are present in the lens epithelial cells, and that each type is distinctly regulated throughout development. While there is a direct correlation between IGF-binding capability and growth rate of the cells, there is less relation to differentiation status and embryo age. Insulin receptors, by contrast, appear to be mostly related to the differentiated state of cells, decreasing sharply in fibers, irrespective of their developmental age.
我们之前曾报道，在鸡胚胎发育的早期阶段（第2 - 3天的全胚胎膜），胰岛素样生长因子（IGF）受体似乎比胰岛素受体更为主要。总体而言，当脑生长速率最高时，[125I]IGF I和II与特异性受体的结合最为显著。在本研究中，我们使用鸡胚胎晶状体，这是一种由单一类型细胞组成的明确组织，来分析胰岛素和IGF I结合的变化是否与细胞生长速率和分化状态的变化相关。我们发现晶状体上皮细胞中同时存在胰岛素受体和IGF受体，并且在整个发育过程中每种受体都受到明显的调控。虽然IGF结合能力与细胞生长速率之间存在直接相关性，但与分化状态和胚胎年龄的关系较小。相比之下，胰岛素受体似乎主要与细胞的分化状态相关，在纤维中急剧减少，而与它们的发育年龄无关。
