Catecholamines, α-, and β-adrenoceptors are not responsible for activation of duodenum motility induced by sympathetic nerve stimulation.

Stimulation of sympathetic nerve in anesthetized dogs not treated with adrenergic blockers more frequently exerted stimulating rather than inhibitory effect on duodenal motility. Blockade of α- and β-adrenoceptors with phentolamine and propranolol, respectively, did not prevent the excitatory action of the sympathetic nerve stimulation, but even potentiated this effect. The data showed that catecholamines as well as α- and β-adrenoceptors are not involved in the excitatory effect of sympathetic origin.