Abstract: | Antisera have been prepared to adrenocorticotrophic hormone, thyrotrophic hormone and growth hormone extracted from human pituitaries and to gonadotrophin, and thyrotrophic hormone extracted from human urine.Precipitin, absorption-precipitin and gel-diffusion tests have been performed with these antisera.No conclusive evidence was obtained of the presence of a hormone-specific antibody in any of the antisera.Cross-reactions occurred indicating the presence of an antigen common to those extracts prepared from the pituitary and a further antigen, or antigens, common to those extracts prepared from the urine.Despite the absence of hormone-specific antibodies fluorescein-labelled samples of the antisera gave staining in the cytoplasm of cells in the anterior pituitary and did not stain other tissues.The implication of these results in the interpretation of tissue localization studies with labelled antisera is discussed. |