NGF and chronic cystitis: This is consistent with previous studies: urothelial TrkA-IR is reduced in both rats with CYP-induced cystitis (39) and urothelium-specific NGF-overexpressing (NGF-OE) mice (11), although TrkA expression may increase in bladder afferents, major pelvic ganglia, and DRG as a consequence of increased NGF availability (39, 45).