Effects of prostaglandin E1 and indomethacin on ACTH, prolactin, GH and LH from rat pituitary in vitro.

Abstract

The effects of prostaglandin E1 (PGE1) and indomethacin (IDM) on the release of several pituitary hormones from the rat pituitary were investigated in vitro. Addition of 2 .mu.g/ml of PGE1 to the medium released growth hormone (GH) and prolactin, but not ACTH and luteinizing hormone (LH). Although the addition of 1 .mu.g/ml of IDM alone had no effect on the basal release of these hormones, IDM diminished the release of ACTH induced by crude rat hypothalamic extracts (HE) or lysine-8-vasopressin (LVP) and the release of LH induced by HE or luteinizing hormone-releasing hormone (LH-RH). A part of PGE1 action might be a direct action on the pituitary gland. PGE1 might release GH and prolactin, whereas IDM might have a direct action on the pituitary gland, which may blunt the release of these pituitary hormones induced by several stimuli.