Baumann G
Department of Medicine, Northwestern University Medical School, Chicago, Ill.
Horm Res. 1991;36 Suppl 1:5-10. doi: 10.1159/000182179.
Human growth hormone (GH) consists of a number of molecular variants which derive from 2 genes, several alternative mRNA splicing mechanisms, and post-translational modifications such as deamidation, acylation, glycosylation, and oligomerization. After secretion, GH binds to two (or possibly more) circulating GH-binding proteins, one of which is a truncated GH receptor. The resulting mixture of GH moieties in plasma is enormously complex, consisting of over 100 molecular states. The various GH forms undergo differential clearance, receptor binding, and complexing with binding proteins, each exhibiting distinct kinetics. The net effect on bioactivity is correspondingly complex, and measurements by immunoassay or receptor assays are complicated by the lack of a homogeneous analyte. GH is best seen as a family of proteins, many of which fulfill as yet unknown functions in biology.
人生长激素（GH）由多种分子变体组成，这些变体源自2个基因、几种可变的mRNA剪接机制以及翻译后修饰，如脱酰胺、酰化、糖基化和寡聚化。分泌后，GH与两种（或可能更多）循环中的GH结合蛋白结合，其中一种是截短的GH受体。血浆中由此产生的GH部分混合物极其复杂，由100多种分子状态组成。各种GH形式经历不同的清除、受体结合以及与结合蛋白的复合，每种都表现出独特的动力学。对生物活性的净效应相应地很复杂，免疫测定或受体测定由于缺乏均一的分析物而变得复杂。GH最好被视为一类蛋白质，其中许多在生物学中仍具有未知功能。
