Fig. 2.
NMDA-type glutamate or neurokinin receptor antagonists prevent experimentally induced coughing in humans and in animals. Coughing was evoked by inhalation of citric acid (humans, pigs, guinea pigs (upper panel)) or capsaicin (rat, guinea pig (lower panel)), or by mechanical probing of the airway mucosa in anesthetized dogs, rabbits and cats. NMDA (dextromethorphan, MK801, APV), NK1 (αNK1; CP99994 or SR140333 (pigs), NK2 (αNK2; SR48968 or NK3 (αNK3; SR142801) receptor antagonists were given systemically (to humans, pigs, dogs, guinea pigs (upper panel)), by icv or central arterial administration (rats, cats, guinea pigs (lower panel)) or by nTS microinjection (rabbits). Comparable effects have been reported with systemic administration of NK3 receptor antagonists in guinea pigs [6,7]. Data are modified from published results [3-5, 10, 39, 69-71].