Amiodarone-induced lung toxicity and the protective role of Vitamin E in adult male albino rat

Amiodarone is a highly effective anti-arrhythmic drug, used in the treatment of cardiac arrhythmias. However, it is of a limited use due its serious side effects especially lung toxicity. This study was designed to investigate the role of vitamin E in ameliorating amiodarone-induced lung toxicity in adult male albino rat. The study was carried out on 24 adult male albino rats, divided into 4 equal Groups: Group I (control), Group II (sham control), Group III (Amiodarone treated) and Group IV (Amiodarone and vitamin E treated). After the end of the experiment, the rats were sacrificed by cervical dislocation, then parts of the rat lungs of each Group were prepared for light microscopic, histochemical study, immune-histochemical and ultrastructural study. Fresh Lung sections were processed for electron microscopic study. The results revealed marked pathological alterations in the rat lungs of Group III: distortion in the pulmonary architecture, mononuclear cellular infiltration, presence of areas of consolidation with alveolar collapse, areas of emphysematous air spaces, marked degeneration of the pneumocytes and increased collagen fibers deposition and marked increase in iNOS immunoexpression. There were marked alterations in the level oxidative markers in the lung homogenates. The ultrastructural study confirmed these changes. Treatment with vitamin E in Group IV revealed noticeable improvement of the histological and ultrastructural architecture of the lung. There was marked improvement in the other parameters. The present study concluded that amiodarone has marked toxic effect on the lung of the adult male albino rat and vitamin E could partially protect the lung against such toxic effects.