Trenkle A
Growth. 1977 Dec;41(4):241-7.
The growth hormone (GH) status of 24 castrated male cattle was studied over a range of body weights by measuring GH in the blood plasma and anterior pituitary and by calculating metabolic clearance (MCR) and secretion rates after injection of GH. As the cattle increased in size, pituitary weight and GH content, MCR of GH and secretion of GH decreased relative to body weight. Plasma concentrations of GH did not decrease as markedly as secretion because MCR/body weight was also lower in the larger animals. At all sizes, more than 99% of the total GH in the body was located in the anterior pituitary. It was calculated that the pituitary releases 0.58% of its GH content per hour. This rate of release did not significantly change with body weight. It is suggested that basal secretion of GH by the anterior pituitary is related to GH content and that, as animals grow, there is gradually less GH available per unit of body mass.
通过测量血浆和垂体前叶中的生长激素（GH），并在注射GH后计算代谢清除率（MCR）和分泌率，研究了24头去势公牛在不同体重范围内的生长激素（GH）状态。随着牛体型的增大，垂体重量和GH含量、GH的MCR以及GH分泌相对于体重均下降。GH的血浆浓度下降不如分泌明显，因为较大动物的MCR/体重也较低。在所有体型下，体内超过99%的总GH位于垂体前叶。经计算，垂体每小时释放其GH含量的0.58%。这种释放速率不会随体重显著变化。提示垂体前叶GH的基础分泌与GH含量有关，并且随着动物生长，每单位体重可利用的GH逐渐减少。
