The effect of various prostaglandins and a prostaglandin synthetase inhibitor on rat anterior pituitary cyclic AMP levels and hormone release in vitro (38475).

(U)Prostaglandins E-1, E2,F-1alpha or F-2 alpha significantly increased the release of GH, with a parallel increase in intracellular cAMP concentrations, while they only protentiated HE-stimulated TSH release. (2) None of the prostaglandins examined consistently effected either the basal or HE-altered release of LH,FSH or prolactin. (3) The prostaglandin synthetase inhibitor, indomethacin, inhibited GH and TSH release and, at high doses of the drug, inhibited prolactin release. In contrast, the drug appeared to potentiate both He and sLRF-stimulated gonadotropin release. It had no significant effect on intracellular cAMP concentration.