The effect of varasurf surfactant on respiratory distress syndrome in rats

Objective Acute respiratory distress syndrome (ARDS) is occurred by disruption of alveolar-capillary membrane and associated with an inflammation process. Methods The effect of varasurf surfactant on respiratory distress syndrome (RDS) in rats was compared to curosurf. RDS was induced in anesthetized and ventilated male Wister rats, using 10 times lung lavage with 3 ml saline. Stepwise increasing air volume was administered and withdrawn from the lung; while, lung pressure was monitored and lung compliance was determined. The study was performed in control, RDS, RDS treated with varasurf and curosurf groups (n = 8). Results Lung compliance was significantly reduced, but total and differential white blood cell (WBC) counts in the blood and the bronchial alveolar lavage fluid (BALF) were increased, and oxidative stress markers in the BALF, lung tissue and serum were changed in RDS group (P < 0.05-P < 0.001). In RDS group treated with varasurf, lung compliance was significantly increased compared to the both untreated and curosurf treated RDS groups (both, P < 0.001). Varasurf treatment improved all measured variables, but curosurf treatment only improved total WBC, eosinophil and lymphocyte counts in the BALF and total WBC and lymphocyte counts in the blood and thiol level and catalase (CAT) activity in the BALF and malondialdehyde (MDA) and thiol levels both in the lung tissue and serum compared to the control group (P < 0.05 to P < 0.001). Conclusion Treatment of RDS rats with varasurf improved lung compliance, lung and systemic inflammation and oxidative stress, which was more prominent than curosurf.