EFFECT OF PYROGALLOL ON THE LUNG

¹ Department of Medicine, University of Sydney, Sydney, NSW, Australia

Pyrogallol (1,2,3-trihydroxybenzene) was administered as a single intravenous dose (20 mg/kg) or as an aerosol in sheep. In normal animals this resulted only in a small consistent rise in lung compliance; other circulatory and respiratory parameters remained unchanged. In animals previously subjected to lung embolism, mismatched blood transfusion or intravenous endotoxin administration, the intravenous injection or inhalation of the same dose of pyrogallol resulted in a marked reduction in pulmonary hypertension and hyperventilation and in a gross rise in lung compliance and arterial oxygen saturation. It is suggested that these effects are produced by relieving smooth muscle constriction around airways and lung vessels. The mode of action of pyrogallol was unrelated to its O-methyl-transferase activity and remained obscure.