Jørgensen J O, Møller N, Wolthers T, Møller J, Grøfte T, Vahl N, Fisker S, Orskov H, Christiansen J S
Department of Internal Medicine (Endocrinology and Diabetes), Aarhus University Hospital, Denmark.
Metabolism. 1995 Oct;44(10 Suppl 4):103-7. doi: 10.1016/0026-0495(95)90229-5.
Apart from being a stimulator of longitudinal growth, growth hormone (GH) regulates fuel metabolism in children and adults. A halfmark is mobilization of lipids, which involves an inhibition of lipoprotein lipase activity in adipose tissue and activation of the hormone sensitive lipase. Suppression of basal glucose oxidation and resistance to insulin are other important effects. This may cause concern during GH substitution in GH-deficient adults, some of whom may present with insulin resistance due to concomitant abdominal obesity. However, there are data to suggest that the GH-induced reduction in fat mass and increase in lean body mass may offset the insulin antagonistic actions of the hormone. The nitrogen-retaining effects of GH seem to involve a direct stimulation of protein synthesis in addition to secondary effects such as generation of insulin-like growth factor-I (IGF-I), hyperinsulinemia, and promotion of lipolysis. Thus, during periods of substrate affluence, GH acts in concert with insulin and IGF-I to promote protein anabolism. Postabsorptively, GH is primarily lipolytic and thereby indirectly protein-sparing. This effect becomes further accentuated with more prolonged fasting. In that sense, GH is unique by its preservation of protein during both feast and famine. These fuel metabolic effects add merit to the principle of GH substitution in hypopituitary adults.
除了作为纵向生长的刺激因子外，生长激素（GH）还调节儿童和成人的能量代谢。其中一个作用是动员脂质，这涉及抑制脂肪组织中的脂蛋白脂肪酶活性并激活激素敏感性脂肪酶。抑制基础葡萄糖氧化和胰岛素抵抗是其他重要作用。在对生长激素缺乏的成年人进行生长激素替代治疗期间，这可能会引起担忧，其中一些人可能由于伴有腹部肥胖而出现胰岛素抵抗。然而，有数据表明，生长激素引起的脂肪量减少和瘦体重增加可能会抵消该激素的胰岛素拮抗作用。生长激素的氮保留作用似乎除了诸如产生胰岛素样生长因子-I（IGF-I）、高胰岛素血症和促进脂肪分解等次要作用外，还涉及直接刺激蛋白质合成。因此，在底物丰富的时期，生长激素与胰岛素和IGF-I协同作用以促进蛋白质合成代谢。在吸收后状态下，生长激素主要是促脂肪分解的，从而间接节省蛋白质。随着禁食时间延长，这种作用会进一步增强。从这个意义上说，生长激素在饱食和饥饿期间都能保护蛋白质，这是其独特之处。这些能量代谢作用为垂体功能减退的成年人进行生长激素替代治疗的原则增添了价值。
