Objective

To revisit a finding, first described in 1978, which documented existence of a pituitary growth factor that escaped detection by immunoassay, but which was active in the established rat tibia GH bioassay.

Methods

We present a narrative review of the evolution of growth hormone complexity, and its bio-detectability, from a historical perspective.

Results

In humans under the age of 60, physical training (i.e. aerobic endurance and resistance training) are stressors which preferentially stimulate release of bioactive GH (bGH) into the blood. Neuroanatomical studies indicate a) that nerve fibers directly innervate the human anterior pituitary and b) that hind limb muscle afferents, in both humans and rats, also modulate plasma bGH. In the pituitary gland itself, molecular variants of GH, somatotroph heterogeneity and cell plasticity all appear to play a role in regulation of this growth factor.

Conclusion

This review considers more recent findings on this often forgotten/neglected subject. Comparison testing of a) human plasma samples, b) sub-populations of separated rat pituitary somatotrophs or c) purified human pituitary peptides by GH bioassay vs immunoassay consistently yield conflicting results.

中文翻译：

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人类的生物活性生长激素：争议，复杂性和概念

目的

为了回顾这一发现，首先在1978年进行了描述，该文献记载了垂体生长因子的存在，该垂体生长因子无法通过免疫测定法检测到，但在已建立的大鼠胫骨GH生物测定法中具有活性。

方法

我们从历史的角度对生长激素复杂性的演变及其生物可检测性进行叙述性回顾。

结果

在60岁以下的人群中，体育锻炼（即有氧耐力和抵抗力训练）是应激源，可以优先刺激生物活性GH（bGH）向血液中的释放。神经解剖学研究表明：a）神经纤维直接支配人的垂体前叶； b）人和大鼠的后肢肌肉传入神经也调节血浆bGH。在垂体自身中，GH的分子变异，体营养异质性和细胞可塑性似乎都在调节该生长因子中起作用。

结论

这篇评论考虑了关于这个经常被遗忘/被忽视的主题的最新发现。比较测试a）人血浆样品，b）分离的大鼠垂体生长激素亚群，或c）通过GH生物测定法与免疫测定法纯化的人垂体肽始终产生矛盾的结果。