Shock wave lithotripsy (SWL) is known to induce oxidative stress and a rapid inflammatory response in renal tissue. The purpose of this study was to determine the location and quantify markers for oxidative stress and inflammation in a porcine model of acute SWL-induced renal injury. The lower pole calyx of left kidneys of female pigs received 2000 shock waves at 24 kV/2 Hz from a Dornier HM3 lithotripter and subsequently monitored for 4 h. Heme oxygenase-1 protein (HO-1) was measured in renal microsomes by Western blot. Renal medulla HO-1/β-actin ratios were 1.186 ± 0.48 for treated pole (F2), 0.293 ± 0.23 for treated kidney upper pole, and 0.122 ± 0.075 for contralateral kidney (n=6). Thus, we observed an eightfold induction of HO-1 in renal medulla at F2 compared to the upper pole medulla of the treated kidney and the contralateral kidney medulla. In contrast, renal cortex at F2 did not show a similar HO-1 induction. The highly localized HO-1 induction in SWL-treated renal medulla parallels our previously reported finding of interleukin-6. These data together suggest that an early inflammatory response and oxidative stress appear primarily in the treated renal medulla within 4 h after SWL. [Work supported by NIH].