Warwick-Davies J, Lowrie D B, Cole P J
Host Defense Unit, Royal Brompton National Heart and Lung Institute, London, United Kingdom.
J Immunol. 1995 Feb 15;154(4):1909-18.
Although many effects of growth hormone (GH) and related factors upon the immune system have been demonstrated, few studies have examined the capacity of these factors to modulate human monocyte function in vitro. Assaying a range of mediators, only GH and prolactin (PRL), at 0.3 to 1.0 micrograms/ml, and growth hormone-releasing hormone (GRH) at very high doses, primed monocytes for enhanced hydrogen-peroxide production (H2O2) in response to PMA. GH-induced priming was not caused by endotoxin, nor by production of lymphokines such as IFN-gamma. Exogenous insulin-like growth factor-I (IGF-I), alone or in combination with GH, was without effect, making it unlikely that GH mediates its effects on monocytes via an autocrine/paracrine action of IGF-I. Monocytes specifically bound radiolabeled GH and contained mRNA for the GH receptor and, in some donors, the PRL receptor. Therefore, GH probably exerts its effects as a human macrophage-activating factor through either GH or PRL receptors, without requiring production of IGF-I.
尽管生长激素（GH）及相关因子对免疫系统的诸多作用已得到证实，但很少有研究检测这些因子在体外调节人单核细胞功能的能力。在检测一系列介质时，仅0.3至1.0微克/毫升的GH和催乳素（PRL）以及非常高剂量的生长激素释放激素（GRH）能使单核细胞在对佛波酯（PMA）产生反应时增强过氧化氢（H2O2）的生成。GH诱导的启动作用并非由内毒素引起，也不是由诸如γ干扰素等淋巴因子的产生所致。单独或与GH联合使用的外源性胰岛素样生长因子-I（IGF-I）均无作用，这使得GH不太可能通过IGF-I的自分泌/旁分泌作用介导其对单核细胞的影响。单核细胞特异性结合放射性标记的GH，并含有GH受体的mRNA，在一些供体中还含有PRL受体的mRNA。因此，GH可能通过GH或PRL受体作为人巨噬细胞激活因子发挥作用，而无需IGF-I的产生。
