EFFECT OF MAGNESIUM ION ON THE RESPONSE OF THE RAT UTERUS TO NEUROHYPOPHYSIAL HORMONES AND ANALOGUES1

摘要: Absolute oxytocic potencies of highly purified neurohypophysial hormones and analogues were determined on isolated rat uteri suspended in van Dyke-Hastings solution. Assays performed bath solutions with without magnesium ions. In a concentration 0.5 mM/1. ions found to augment the response U.S.P. Standard, oxytocin, lysine arginine vasopressins all tested, but there was considerable variation between substances degree which this potentiation occurred. Advantages inherent solution Dyke Hastings are discussed, reasons presented for utilizing assays oxytocin posterior pituitary extracts. DALE'S discovery action extract (1) followed 1913 by Dale Laidlaw's description method assaying such extracts isolated, virgin guinea pig (2).