Protective Role of Angiotensin II Type 1 Receptor Blocker on Short Time Effect of Oleic Acid Induced Lung and Kidney Injury

Backgrounds: Acute respiratory distress syndrome (ARDS) causes high mortality rate in clinic, and the pathogenesis of this syndrome may interact with renin angiotensin system (RAS) components. The main objective of this study was to determine the protective role of AT1R antagonist (losartan) on oleic acid (OA) induced ARDS and kidney injury. Methods: The animal model of ARDS was performed by intravenous administration of 250 μl/kg oleic acid (OA). Male and female rats were subjected to received intravenously vehicle (saline, groups 1 and 4), OA (groups 2 and 5), or losartan (10 mg/kg) plus OA (groups 3 and 6), and six hour later, the measurements were performed. Results: Co-treatment of OA and losartan increased the serum levels of blood urea nitrogen significantly ( P < 0.05) and creatinine insignificantly in both gender. However, the OA induced kidney damage was decreased by losartan significantly in male ( P < 0.05) and insignificantly in female rats. In addition, co-treatment of OA and losartan decreased lung water content significantly in male rats ( P < 0.05). Based on tissue staining, no significant difference in lung tissue damages were observed between the groups, however some exudate were observed in lung male rats treated with OA alone which were abolished by losartan. Conclusions: Losartan may protect the kidney and lung against OA induced tissue injury in male rats. This protective action is not certain in female rats.