Subchronic pulmonary inflammation and fibrosis induced by silica in rats are attenuated by amiodarone.
Blake-TL; DiMatteo-M; Antonini-JM; McCloud-CM; Reasor-MJ
Exp Lung Res 1996 Jan; 22(1):113-131
A study was conducted examining the efficacy of amiodarone in attenuating subchronic lung injury and fibrosis induced by silica (14808607). Silica was instilled intratracheally into Fisher-344- rats that had been pretreated with amiodarone for 2 weeks. Amiodarone was continued until the rats were sacrificed 60 days after silica instillation. Amiodarone reduced silica induced increases in the ratio of lung weight to body weight and lung hydroxyproline content by 57% and 68%, respectively; however, both of these values remained increased compared with controls. Histopathologically, amiodarone eliminated the granulomatous response to silica; alveolar histiocytosis was a feature of both silica and silica plus amiodarone treated rats. Amiodarone also decreased the percentage of neutrophils, the level of albumin, and the activities of beta-glucuronidase and lactate-dehydrogenase in bronchoalveolar fluid; none of these values was reduced to control levels. Silica treated rats also demonstrated significant increases in lung concentrations of amiodarone and desethylamiodarone compared with controls instilled with saline. These increases were thought to be associated with silica induced increases in phospholipids. The authors conclude that amiodarone attenuates pulmonary fibrosis and inflammation induced by silica in the rat.
NIOSH-Publication; NIOSH-Cooperative-Agreement; Pulmonary-system-disorders; Silica-dusts; Pharmaceuticals; Lung-fibrosis; Enzyme-activity; Laboratory-animals
Experimental Lung Research
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