Kashimata M, Hiramatsu M, Minami N
Department of Pharmacology, School of Dentistry, Meikai University, Saitama, Japan.
J Endocrinol. 1989 Oct;123(1):75-81. doi: 10.1677/joe.0.1230075.
The effect of human GH (hGH) on hepatic epidermal growth factor (EGF) receptors in the rat was investigated. Continuous administration of hGH through an osmotic minipump, mimicking the female pattern of GH secretion, to normal male rats reduced the binding of 125I-labelled EGF to hepatic membranes to the normal female levels. The same treatment of hGH applied to hypophysectomized males had no apparent effect on EGF binding. Intermittent s.c. administration of hGH twice a day (every 12 h), mimicking the male pattern of GH secretion, to hypophysectomized male and/or normal female rats, caused a significant increase in EGF binding to the levels of normal male rats. Scatchard analysis of the binding data clearly showed that the change in EGF binding was due to a change in the number of EGF receptors. The results on the affinity labelling and phosphorylation of EGF receptors were in good agreement with those showing differences in the number of EGF receptors among the experimental groups. These results indicate that the number of hepatic EGF receptors in the rat is regulated by the differential secretory rhythm of pituitary GH between the sexes.
研究了人生长激素（hGH）对大鼠肝脏表皮生长因子（EGF）受体的影响。通过渗透微型泵持续给予hGH，模拟雌性生长激素分泌模式，对正常雄性大鼠进行处理，结果显示，125I标记的EGF与肝细胞膜的结合减少至正常雌性水平。对垂体切除的雄性大鼠进行同样的hGH处理，对EGF结合无明显影响。对垂体切除的雄性和/或正常雌性大鼠，每天皮下注射hGH两次（每12小时一次），模拟雄性生长激素分泌模式，导致EGF结合显著增加至正常雄性大鼠水平。对结合数据进行Scatchard分析清楚地表明，EGF结合的变化是由于EGF受体数量的改变。EGF受体的亲和标记和磷酸化结果与显示各实验组EGF受体数量差异的结果高度一致。这些结果表明，大鼠肝脏EGF受体的数量受两性垂体生长激素分泌节律差异的调节。
