THE UNITY OR MULTIPLICITY OF THE AUTACOIDS OF THE POSTERIOR LOBE OF THE PITUITARY GLAND

Abstract

Three fractions of pituitary posterior lobe extract were made and their relative oxytocic, pressor and renal activities determined, using an isolated guinea pig uterus for the 1st, pithed intravenously injected cats for the 2nd and for the 3rd, a bitch with a permanent bladder fistula. She was kept on uniform diet and injected intravenously once in each experiment. The pressor and oxytocic activities are shown to have a widely differing distribution after normal butyl alcohol extraction and the renal closely follows the pressor in the same preparation. The separation by extraction of the oxytocic activity from the renal and pressor is explained by assuming that the autacoid responsible for the former is chemically separate from that responsible for the latter.