Gluckman P D, Butler J H
J Dev Physiol. 1985 Dec;7(6):405-9.
Studies were performed to investigate the possible role of pituitary factors on the regulation of circulating concentrations of insulin-like growth factor-I and -II in the midgestation sheep fetus. Four fetuses were decapitated at 59-64 days of gestation and fetal serum obtained at sacrifice at 90-102 days of gestation. Insulin-like growth factor-I and -II concentrations were similar in these samples to those from 6 control fetuses (83-102 days). A further 4 fetuses were studied following electrolytic destruction of the median eminence of the hypothalamus at 108-110 days of gestation. Four sham operated controls were also studied. Circulating growth hormone concentrations were markedly reduced (P less than 0.01) by destruction of the median eminence. However neither insulin-like growth factor-I nor -II levels differed from those of sham operated fetuses. We conclude that, in the midgestation fetal sheep, growth hormone is not essential for the maintenance of circulating concentrations of insulin-like growth factor-I or -II.
开展了多项研究，以探讨垂体因子在调节妊娠中期绵羊胎儿循环中胰岛素样生长因子-I和-II浓度方面可能发挥的作用。在妊娠59 - 64天时，对4只胎儿进行断头处理，并在妊娠90 - 102天时处死时获取胎儿血清。这些样本中胰岛素样生长因子-I和-II的浓度与6只对照胎儿（83 - 102天）的样本相似。在妊娠108 - 110天时，对另外4只胎儿进行下丘脑正中隆起的电解破坏后进行研究。还研究了4只假手术对照胎儿。正中隆起破坏后，循环生长激素浓度显著降低（P < 0.01）。然而，胰岛素样生长因子-I和-II的水平与假手术胎儿的水平并无差异。我们得出结论，在妊娠中期的绵羊胎儿中，生长激素对于维持循环中胰岛素样生长因子-I或-II的浓度并非必不可少。
