Effect of angiotensin II on the proliferation of mammotrophs from the adult rat anterior pituitary in culture.
We measured the influence of prolactin-releasing neuropeptides on mammotroph proliferation in cultures of rat adenohypophysis cells using flow cytometry. Angiotensin II (AII) increased mammotroph proliferation. Other peptides with hormone-releasing activities did not promote growth. Tamoxifen inhibited mammotroph proliferation in control and AII-containing cultures and the inhibition was reversed with beta-estradiol. Saralasin, an AII receptor antagonist, suppressed not only AII-induced mammotroph proliferation but also luteinizing hormone-releasing hormone (LHRH)-induced proliferation. These results suggest that hypothalamic LHRH stimulates AII release from gonadotrophs and that AII, with estrogen, controls mammotroph proliferation in rat pituitary.
Shinkai
T
T
Department of Cell Biology, Tokyo Metropolitan Institute of Gerontology, Japan.
Ooka
H
H
D000804:Angiotensin II / Q000494:pharmacology* / Q000502:physiology; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D005434:Flow Cytometry; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D009479:Neuropeptides / Q000494:pharmacology; D010903:Pituitary Gland, Anterior / Q000166:cytology*; D011388:Prolactin / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012504:Saralasin / Q000494:pharmacology; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology
D004967:Estrogens; D009479:Neuropeptides; D000804:Angiotensin II; D007987:Gonadotropin-Releasing Hormone; D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin; D012504:Saralasin