Acquafredda A, Murrieta D, Schimpff R M, Donnadieu M, Job J C
INSERM U 188, Paris, France.
Horm Metab Res. 1988 Sep;20(9):570-3. doi: 10.1055/s-2007-1010887.
The binding of insulin-like growth factor I (IGF I) on red blood cells has been studied in 13 children aged 8 months to 11 years and in 10 adults. The Scatchard analysis showed a curvilinear regression. In adults, the specific binding was 4.1% of the tracer, the mean number of high affinity receptor sites per cell (Ro1) being 0.88 (K1 = 10.74 nM-1) and the mean number of low affinity receptors sites (Ro2) per cell being 7.14 (K2 = 0.37 nM-1). In children the specific binding ranged from 3 to 6.5%. Ro1 ranged from 0.40 to 3.13 (K1 from 3.48 to 13.61 nM-1). Ro2 ranged from 2.88 to 17.25 (K2 from 0.03 to 0.65 nM-1). The most striking fact was the close positive correlation between the specific binding and the age of children (r = 0.914, P less than 0.001). These data suggest that the high growth velocity of young children, concomitant with the low plasma levels of IGF I which are physiological during infancy and early childhood, does not result from an increased binding of IGF I to cell receptors.
对13名年龄在8个月至11岁的儿童和10名成年人的红细胞上胰岛素样生长因子I（IGF-I）的结合情况进行了研究。Scatchard分析显示为曲线回归。在成年人中，特异性结合为示踪剂的4.1%，每个细胞高亲和力受体位点的平均数（Ro1）为0.88（K1 = 10.74 nM-1），每个细胞低亲和力受体位点的平均数（Ro2）为7.14（K2 = 0.37 nM-1）。在儿童中，特异性结合范围为3%至6.5%。Ro1范围为0.40至3.13（K1为3.48至13.61 nM-1）。Ro2范围为2.88至17.25（K2为0.03至0.65 nM-1）。最显著的事实是特异性结合与儿童年龄之间存在密切的正相关（r = 0.914，P < 0.001）。这些数据表明，幼儿的高生长速度，与婴儿期和幼儿期生理状态下较低的血浆IGF-I水平相伴，并非由IGF-I与细胞受体结合增加所致。
