[Effect of steroid hormones and noradrenaline on somatotropin hormone secretion by primary cultures of hypophyseal cells of rats of various ages].

Dexamethasone and aldosterone in concentrations 10(-8) to 10(-6) stimulated STH secretion by hypophyseal cells of neonatal and adult rats under conditions of prolonged (72 h) incubation of primary cultures. Corticosterone and progesterone had a stimulating effect on STH release by hypophyseal cells. Long exposure of cultured suckling rat cells to dexamethasone resulted in increase of STH basal secretion and enhanced the stimulating effect of low concentration (10(-7) mole) of noradrenaline on STH release during a subsequent short (2 h) incubation. The results permit us to suggest that development of hypophyseal somatotropic function observed in the postnatal period may be to a certain measure explained by combined effects of corticosteroids and catecholamines.