Although we did not investigate the expression of the vascular endothelial growth factor (VEGF), which plays a significant role in remodeling of blood vessels, previous studies reported changes in VEGF and/or VEGF receptors and signaling pathways in the bladder of patients with IC/BPS (Tamaki et al., 2004; Saban R. et al., 2008; Kiuchi et al., 2009), and rodent models of bladder inflammation (Saban M. R. et al., 2008; Saban R. et al., 2008). This evidence concerns the gene VEGFA and Bartsocas-Papas syndrome 1.