THE EFFECTS OF SODIUM CROMOGLYCATE ON HISTAMINE AEROSOL‐INDUCED REFLEX BRONCHOCONSTRICTION IN THE ANAESTHETIZED DOG

Abstract

The effects have been studied of sodium cromoglycate (SCG), given by aerosol or intravenously, on reflex bronchoconstriction induced by histamine aerosol in the anaesthetized dog. Four breaths of an aerosol generated from a 2% solution of SCG significantly inhibited the vagally mediated increase in total lung resistance (RL) produced by histamine. SCG given intravenously as bolus injections (5–500 μg/kg) produced a dose‐dependent reversal of a sustained reflex bronchoconstriction induced by histamine aerosol. Propranolol (500 μg/kg) did not prevent this reversal. SCG did not inhibit the increase in RL produced by supramaximal electrical stimulation of a vagus nerve. The possibility is discussed that SCG may reduce the activity of lung irritant receptors in the anaesthetized dog. 1977 British Pharmacological Society