ABSTRACT
Six hours after inhalation pulmonary injury,the pulmonary microvascular permeability (PMVP),pulmonary malondialdehyde (MDA) level,superoxide dismu-tase activity (SOD),the contents of protein and leucocytes in broncho-alveolar lavage fluid(BALF),and serum MDA level were determined in rats pretreated with allopurinol.In addition,the pathological changes of the lung tissues were also studied.It was found that early administration of allopurinol resulted in marked reduction of PMVP,and the protein content and leucocyte count in BALF.His-topathological examinations revealed that allopurinol could reduce the leucocyte accumulation in pulmonary vessels,interstitial leucocyte infiltration,interstitial and alveolar edema and hemorrhage,and vascular congestion.The serum and pulmonary levels of MDA also markedly decreased.The changes of pulmonary level of MDA were parallel to those of PMVP,and the protein content and leucocyte count in BALF in time course and in degree.The results listed here imply that the mechanism of the therapeutic effects of allopurinol on inhalation pulmonary injury is to reduce the production of superoxide anions through the inhibition of xanthine oxidase,in turn to inhibit the peroxidation of pulmonary lipids to alleviate pulmonary damage.