Comparative Study of Human Fetal, Normal Adult, and Somatotropic Adenoma Pituitary Function in Tissue Culture*

Abstract

Tissue from 14 somatotropic adenomas, 2 normal adult pituitaries, and 16 fetal pituitaries (10–20 weeks gestation) was maintained in culture for 2 weeks. The secretion of GH, PRL, LH, and TSH into culture medium was studied both in the basal state and in response to acute 3-h exposure to TRH, apomorphine, somatostatin (SRIF), LRH, and theophylline. The findings were compared with results of in vivo dynamic pituitary function tests performed in the adult patients before transsphe-noidal surgery. The adenoma tissue secreted 0.5 to more than 20 μg GH/ml culture medium-day; six adenomas also secreted measurable amounts of PRL. The normal adult pituitary tissue secreted significant amounts of all hormones measured. The fetal pituitaries also secreted all of the hormones, but PRL, TSH, and LH were barely detectable. Hormone release into culture medium declined rapidly in the first 3–4 days and then remained stable until the end of the culture period. TRH (2.8 × 10–6 M) inhibited GH secretion by fetal and normal...