Hormone Synthesis and Release from Human Fetal Adenohypophysesin Vitro

Abstract

The hormone synthesis and release in vitro from the adenohypophysis of 40 normal human fetuses was studied by radioimmunoassay and protein incorporation of C¹⁴-l-leucine. Within the first 20 days in vitro, the release of GH, prolactin (PRL), LH, FSH, TSH, ACTH and MSH decreased to low or undetectable levels. The production of PRL and MSH, after the initial fall, spontaneously increased with time in culture to sustained and elevated levels. For all the hormones the quantity released was related to the gestational age of the donor fetus. In the cases of LH and FSH the hormonal release was not only related to the age of the fetus but also to the sex. The duration of FSH release in vitro was significantly longer (p > 0.005) for female pituitary cultures than for males. The release of pituitary hormones was detected as early as 5 weeks fetal life. In some fetuses, abnormal release of certain hormones in vitro could be relatd to demonstrable fetal abnormalities. These results indicate that the fetal pituitary is a dynamic endocrine organ throughout gestation and may play an active role in normal fetal development.