human placental extract ameliorates structural lung changes iinduced by amiodarone in rats

amiodarone is used in treatment of cardiac arrhythmias. therapeutic use of amiodarone is limited by its side effects, including pulmonary toxicity. human placenta extract (hpe) contains a variety of bio-active substances. thus, the present study aimed to quantitatively evaluate the protective effects of hpe on the structural lung changes induced by amiodarone using stereological methods. sprague-dawley male rats were divided into four groups. the first, second, and third groups received no treatment, amiodarone (100 mg/kg, i.p.), and hpe (500µl/kg, i.p.), respectively. the fourth group was treated with amiodarone+hpe. the animals' lungs were removed after 10 days. the lung volume was estimated using the cavalieri principle on the embedded and cut tissue and corrected for shrinkage. the volume density of the parenchyma, alveolar space, and septa were estimated using point-counting method. the surface area of the alveoli, the volume-weighted means alveoli volume, and mean septum thickness were also estimated in all groups. the total volume and thickness of the alveolar septum were increased by 40% and 28%, respectively. however, the total volume of the alveolar space was decreased by 31% in the amiodarone treated-rats. the mean alveolar volume was decreased by 64% on the average in the amiodarone treated group. yet, these changes were not detected in the amiodarone+hpe group. moreover, rbc accumulation in the alveolar space and septa was ameliorated after hpe treatment. hpe can protect the lung tissue from the structural changes induced by amiodarone.