Acute DA administration induced renal cortical NGAL expression. (A) NGAL IHC at 2, 24, or 72 hours after DA or vehicle treatment in the renal cortex as viewed in low- (top panels; 5× objective) or higher-powered images (bottom panels; 20× objective). Diaminobenzidine chromogen with hematoxylin counterstain was used. Veh, vehicle. (B) NGAL IHC at 2 or 72 hours after DA or KYNA+DA treatment (20× objective). (C) uNGAL excretion 72 hours after DA or KYNA+DA treatment. *Data were significantly different from the 0-hour time point. #KYNA+DA treatment was significantly different from DA (n=3, P<0.05, ANOVA followed by Newman–Keuls for individual group comparisons).