Ischemia/reperfusion (I/R) induced acute renal failure (ARF), causes renal functional and histological disorders. This study investigated the effect of oral Rosemary extract on ARF disorders in rat. Forty male Sprague-Dawley rats were used in 4 groups (n=10) as control, sham, I/R with gavage feeding normal saline, and I/R with gavage feeding of 8% aqueous extract of Rosemary (10 ml/kg/day). ARF was induced by bilateral renal artery and vein occlusion for 30 min. Reperfusion period was continued for 24 h. Blood pressure and renal blood flow of rats were measured using a power lab system (AD instruments). After placing the rats into metabolic cages, urine sampling was done. Plasma samples were obtained and after removing both kidneys and staining kidney sections, histological studies were performed. Data were analyzed using SPSS software version 11.5. The comparison between Rosemary and vehicle groups indicated significant reduction in [Cr]p (P< 0.001), [BUN]P (P < 0. 01), UNaV° (P < 0.001), and significant increase in UKV° (P< 0.001) in the Rosemary group. Oxidative stress studies indicated the ability of the aqueous extract of Rosemary to decrease malondialdehyde (MDA) and increase ferric reducing antioxidant power (FRAP) in comparison with the I/R group. Histopathological analyses indicated significant decreases in vessels congestion, tubules disorder, and space of Bowman's capsule in the Rosemary group in comparison with the vehicle groups. Post treatment with Rosemary aqueous extract protects the rats against histological injury and functional impairment induced by 24 h I/R.
