Dopaminergic control of the cough reflex as demonstrated by the effects of apomorphine

The effect of apomorphine on the cough reflex induced by electrical stimulation of the superior laryngeal nerve was studied in cats anesthetized with pentobarbital. Intravenous administration of apomorphine in doses which ranged from 0.1 to 1.0 mg/kg decreased the number of coughs in a dose-dependent manner. Haloperidol (0.3 mg/kg i.v.) did not significantly change the number of coughs. However, haloperidol administered 15 min prior to administration of apomorphine abolished the apomorphine-induced decrease in the number of coughs. These results suggest that dopaminergic mechanisms could have an important role in the regulation of the cough reflex.