 This study investigates the effects of unilateral ureteral obstruction, UO, on renal hemodynamics, and the role of angiotensin II, Ong II, receptor antagonists in rats. Losartan and PD123319 were used to block the effects of Ong II in the kidney. The results show that graded doses of Ong II caused a decrease in renal blood flow, RBF, increase in renal vascular resistance, RVR, and mean arterial pressure, MAP, in all groups. However, Losartan treatment reduced the RBF, RVR, and MAP responses to Ong II in comparison to vehicle or PD123319 treated groups. Additionally, the RBF, RVR, and MAP responses to Ong II were not similar in sham. UO and REO rats treated with Losartan. This suggests that Losartan may be effective in reducing the renal damage associated with UO. This article was authored by Jalal Hassan Shahi, Mariam Maliki, and Mehdi Nematbacksh. We are article.tv. Links in the description below.