Long-term in-vitro maintenance of growth hormone secretion from human somatotrophinomas with cortisol, and its effects on growth hormone-releasing factor.
The effect of cortisol (206 nmol/l) on GH secretion from enzymatically dispersed human somatotrophinoma cells in long-term culture was studied using adenomas from 13 patients with acromegaly. Basal GH secretion from cultures of three out of five tumours measured during periods of 4 hours declined to less than 10 mu u. GH/culture within 21 days. Secretion from two other tumours measured during 24 h also declined but GH concentrations were still readily detectable (greater than 100 mu u./culture) by 28 or 58 days after cell dispersal. The decline in GH secretion was reversed in all seven tumours when cultures were maintained in cortisol-supplemented medium (CM), 4-h secretion rates being increased or retained at greater than or equal to 100 mu u./culture for as long as the studies were continued (range 18-291 days), and 24-h secretion rates at greater than 1000 mu u./culture (range 28-58 days). GH secretion and content from cultures of two additional somatotrophinomas were increased by treatment with cortisol for 5 or 9 days but there was no concomitant effect on cell number. During long-term maintenance of cultures in CM (range 5-40 days), cortisol partially or completely blocked the 4-h GH response to a test dose of GH-releasing factor (GRF) (20 nmol/l) in five out of six tumours, and to a dose range of GRF (0.01-20 nmol/l) in two of them.(ABSTRACT TRUNCATED AT 250 WORDS)
D000236:Adenoma / Q000378:metabolism*; D002478:Cells, Cultured; D003470:Culture Media; D013006:Growth Hormone / Q000378:metabolism*; D013007:Growth Hormone-Releasing Hormone / Q000494:pharmacology*; D006801:Humans; D006854:Hydrocortisone / Q000494:pharmacology*; D010187:Pancreatic Hormones / Q000494:pharmacology*; D010911:Pituitary Neoplasms / Q000378:metabolism*; D013268:Stimulation, Chemical; D013997:Time Factors
D003470:Culture Media; D010187:Pancreatic Hormones; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone; D006854:Hydrocortisone