Optical density of inducible nitric oxide synthase (iNOS) and aquaporin-3 (AQP-3) between cystitis group and control group. Bars are mean±SE. White bars are control group, Black bars are interstitial cystitis group. A: iNOS, B: AQP-3, m: mucosa, sm: submucosa, M: muscle, *: p<0.05 vs. control group.