“Cholinoceptor antagonists hexamethonium and atropine) and α2‐ and β2‐adrenoceptor antagonists (yohimbine and ICI 118,551) partially reversed the effects produced by melatonin and 5‐MCA‐NAT, suggesting the possible involvement of cholinergic and noradrenergic systems in the hypotensive actions mediated by melatonin agonists.”