Salivation induced by prostaglandin F 2 and modification of the response by atropine and physostigmine.

1. Administration of PGF(2alpha) to the anaesthetized dog produced dose-related salivation accompanied by weak pressor and negative cardiac chronotropic effects. Injection of PGE(1) did not produce salivation.2. Electrical stimulation of the chorda tympani nerve or injection of PGF(2alpha) produced salivary responses which were not affected by pretreatment with phentolamine, but were abolished by pretreatment with atropine. Treatment with hexamethonium reduced the response to nerve stimulation but did not alter the response to PGF(2alpha).3. Pretreatment with physostigmine augmented the salivary response to both nerve stimulation and PGF(2alpha).4. These experiments suggest that salivation produced by PGF(2alpha) is probably due in part, to liberation of acetylcholine from cholinergic nerve terminals. These results are consistent with previously proposed modulatory functions of prostaglandins on neurotransmission.