The persistence of a depressor response to oxytocin in the fowl after denervation and blocking agents.

The effects of oxytocin and vasopressin on the blood pressure of the fowl have been studied after surgical or chemical interruption of parts of the central and peripheral nervous systems, and after the administration of stilboestrol and progesterone. An augmented and prolonged depressor response to oxytocin was seen after atropine, bretylium, tetraethylammonium or decapitation, but not after decerebration, dihydroergotamine or dibenamine. There was a tendency for the pressor action of vasopressin to disappear after decapitation, decerebration, and all the blocking agents used, except tetraethylammonium. The differences between these results and those which have been obtained in rats are discussed.