The expression levels of the sensory receptors, TRPV1, TRPV4, and sigma-1; the inflammatory proteins, P38 and tryptase; and the pro-apoptotic proteins, caspase-3 and BAD, were significantly increased in the urothelium of IC/BPS patients compared with the expression levels in the urothelium of the controls. Here, TRPV4 is linked to Bartsocas-Papas syndrome 1.