INHIBITORY EFFECTS OF ANTIRAT PITUITARY SERUM (APS) ON HYPOPHYSECTOMIZED RATS INJECTED WITH PITUITARY HORMONES

Abstract

This study concerns the effects of the rat pituitary antiserum (APS) and of bovine growth-hormone (STH) anti-serum upon the organs of hypophysectomized rats. Hormonal stimulation was produced by the injection of rat pituitary homogenate or purified hormones. By using the tibial width test and organ weights, hormonal stimulation and the degree of inhibition by antisera were evaluated. It was found that APS, when injected in conjunction with rat pituitary homogenate into hypophysectomized rats, inhibited the activities of growth and gonadotrophic hormones. Similar inhibitory effect was obtained when APS was injected in conjunction with bovine STH into hypophysectomized rats. Bovine STH antiserum was found to inhibit stimulatory effect of rat pituitary. Serological studies by complement fixation and precipitin tests exhibited specific antibodies in APS and in bovine STH antiserum against their homologous antigens. The Ouchterlony technique revealed some common components in rat and bovine pituitary antigens.