Possible role of leukotrienes in propranolol-induced airway hyperreactivity in sensitized guinea-pigs.

In anesthetized guinea-pigs previously sensitized to ovalbumin by intratracheal immunization, the intravenous administration of propranolol (3.1 mg/kg) produced an increase in the respiratory insufflation pressure induced by ovalbumin. Atropine (2 mg/kg), zolertine (1 mg/kg) and indomethacin (3.1 mg/kg) did not antagonize the propranolol-induced airway hyperreactivity. Indomethacin at higher dose (10 mg/kg) and BW755c (10 mg/kg) decreased the potentiation of the respiratory insufflation pressure to ovalbumin. Our results suggest that besides the beta-blockade, propranolol-induced bronchial hyperreactivity to ovalbumin in sensitized guinea-pigs could be mediated by leukotrienes.