BDNF and chronic cystitis: Cross-validation of these findings in alternative models of cystitis via a number of induction methods and a range of species, such as other irritant-induced cystitis models, stress models, and naturally occurring cystitis in cats (70, 73-75), is especially prudent given the evident complexity of neurotrophin signaling in the bladder and spectrum of symptomatologies encompassed by IC/BPS.