Studies of carbachol-induced wet-dog shake behavior in rats

Intraventricular administration of carbachol chloride evoked wet-dog shakes (WDS) in rats in a dose-related manner. WDS induced by carbachol at the dose of 20 microgram were antagonized by scopolamine, atropine, cyproheptadine, morphine, clonidine, phentolamine, haloperidol, and L-5-hydroxytryptophan (5-HTP). Methergoline, propranolol, bicuculline, and aminooxyacetic acid had no effect on carbachol-induced shaking behavior. The present experiments show the existence of different types of shaking behavior, not exclusively related to the stimulation of central 5-HT structures.