Atropine prevents the reflex tracheal relaxation arising from the stimulation of intestinal and skeletal muscle afferents in dogs.
Using cholinergic and beta-adrenergic antagonists, we characterized the efferent arms of two reflex arcs that relax tracheal smooth muscle in dogs. The reflex arcs investigated were activated by the capsaicin-induced stimulation of afferent endings in the intestine and in the hindlimb. We found that the reflex tracheal relaxations were due to a withdrawal of a tonic cholinergic input. Beta-adrenergic pathways played little role in causing these reflex responses.
D000344:Afferent Pathways / Q000502:physiology*; D000818:Animals; D001285:Atropine / Q000494:pharmacology*; D002211:Capsaicin / Q000494:pharmacology; D004285:Dogs; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000502:physiology*; D009132:Muscles / Q000294:innervation; D011433:Propranolol / Q000494:pharmacology; D012018:Reflex / Q000187:drug effects*; D014132:Trachea / Q000187:drug effects* / Q000502:physiology
D001285:Atropine; D011433:Propranolol; D002211:Capsaicin