The pharmacology of a new oxytocic principle from ox hypothalamus.
1. An oxytocic substance has been isolated from ox hypothalamus by successive gel filtration on Sephadex G-25 and Sephadex G-50, and its pharmacology has been examined on three smooth muscle preparations.2. The substance has the same order of potency on rat uterus, guinea-pig ileum, and hen rectal caecum.3. The action of the substance on rat uterus was not abolished by thioglycollate.4. Atropine (1.0 mug/ml.), phenoxybenzamine (0.1 mug/ml.) and mepyramine (1.0 mug/ml.) did not block the smooth muscle action of the substance.5. Drug action, relative potency, and log dose-response relationships distinguish the substance from 5-hydroxytryptamine, acetylcholine, oxytocin, vasopressin, angiotensin amide, bradykinin, and purified preparations of substance P.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology; D002417:Cattle; D005260:Female; D007031:Hypothalamus / Q000032:analysis*; D007082:Ileum / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D010120:Oxytocics / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D010121:Oxytocin / Q000037:antagonists & inhibitors / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D051381:Rats; D013864:Thioglycolates / Q000494:pharmacology; D014599:Uterus / Q000187:drug effects
D010120:Oxytocics; D013864:Thioglycolates; D010643:Phenoxybenzamine; D010121:Oxytocin; D001285:Atropine; D001920:Bradykinin