ANTI-OESTROGENIC EFFECTS OF NAFOXIDINE ON THE SYNTHESIS OF DNA BY THE RAT PITUITARY GLAND

Abstract

Department of Medicine, University of Queensland, Clinical Sciences Building, Royal Brisbane Hospital, Queensland 4029, Australia Received 25 October 1977 One of the principal actions of oestrogens on their target organs is stimulation of the synthesis of DNA and cell division. In the rat pituitary gland, anti-oestrogens inhibit the oestrogen-induced increase in weight (Schreiber, Přibyl & Roháčová, 1972) and prevent the rise in the level of serum prolactin induced by oestradiol-17β (Jordan, Koerner & Robinson, 1975). The effects of anti-oestrogens on the synthesis of DNA by the pituitary gland have not been described. The experiments reported here show that the anti-oestrogen nafoxidine completely inhibits the synthesis of DNA and affects the secretion of growth hormone (GH) and prolactin in the male rat. Male Sprague–Dawley rats, 100 days old, were allowed free access to a pelleted diet and water and were maintained in a controlled environment (12 h light, 12 h darkness).