Thomopoulos P, Postel-Vinay M C, Testa U, Guyda H J, Posner B I
Endocrinology. 1981 Mar;108(3):1087-90. doi: 10.1210/endo-108-3-1087.
Rat reticulocytes possess receptors for an insulin-like somatomedin peptide ILAs. At 20 C, pH 7.4 and 10(8) cells per ml, the binding of 125I-ILAs reached a steady-state at 120 min. Binding was partially reversible at 20 C and totally reversible at 37 C. Insulin did not compete with ILAs at concentrations as high as 10 microgram/ml. Insulin-like growth factor II (IGF II) competed with the same potency as ILAs itself, while insulin-like growth factor I (IGF I) was five times less potent. The optimum pH for 125I-ILAs binding was 8.5. Mature erythrocytes possessed seven times less binding sites than reticulocytes. These data suggest that the somatomedins might mediate the effect of growth hormone on erythropoiesis.
大鼠网织红细胞拥有一种胰岛素样生长调节素肽（ILA）的受体。在20℃、pH 7.4和每毫升10⁸个细胞的条件下，¹²⁵I-ILA的结合在120分钟时达到稳态。在20℃时结合部分可逆，在37℃时完全可逆。胰岛素在高达10微克/毫升的浓度下不与ILA竞争。胰岛素样生长因子II（IGF II）与ILA本身具有相同的竞争效力，而胰岛素样生长因子I（IGF I）的效力则低五倍。¹²⁵I-ILA结合的最适pH为8.5。成熟红细胞的结合位点比网织红细胞少七倍。这些数据表明生长调节素可能介导生长激素对红细胞生成的作用。
