48 Using a selective prostaglandin EP3 receptor antagonist selectively attenuated responses of mechanosensitive afferent nerves to urinary bladder distention and bladder

nociception either at central nervous system or at the peripheral level.49 High dose of protamine sulphate infused to rats intravesically for 2 weeks results in a loss of upper layer of urothelial cells, an increased of mast cells and PGE2 level, increase of urinary frequency,and decrease of voided volume.50 Urinary PGE2 levels were elevated in patients with UTI andsuccessful treatment for UTI lowers urinary PGE2 levels.51 In patients with OAB, urinary PGE2 level was also found to significantly increase and the PGE2 levels negatively correlated with

the maximum cystometric capacity.35 Recently, Yamaguchi et al. found that the urinary PGE2 level was significantly higher in patients with Inhibitor Library brain disease, with or without OAB symptoms, than in healthy controls. However, urinary see more NGF and substance P were not significantly associated with OAB as a result of brain disease.52 The role of urinary PGE2 on OAB needs further investigation. Adenosine triphosphate (ATP) and nitric oxide (NO) are released from the urothelium in the bladder. Munoz et al.53 reported that ATP release has a positive correlation, while NO release has a negative correlation with bladder contraction frequency in the rat. They suggested that urinary ATP/NO ratio may be a clinically relevant biomarker to characterize the extent of bladder dysfunction. Sugaya et al.54 further investigated whether the improvement of LUTS and urinary ATP level were related. Improvement of LUTS by treatment with alpha-1 receptor antagonist or

anti-muscarinic agent was related to decrease of urinary ATP/Cr ratio in patients with BPH or OAB. They suggested that measurement of urinary ATP can be used as a marker of pathologic bladder function. Tyagi and Chancellor proposed the hypothesis that local inflammation is a cause of and plays a central role in the etiology of the OAB. Tyagi et al.55 subjected urine from OAB patients through a test screen containing antibodies against 32 cytokines, chemokines, and growth factors to identify proteins with altered levels in their urine. A chronic feature of OAB makes it likely to be correlated with inflammation Exoribonuclease resulting from the body’s release of inflammatory cytokines as a result of irritation or injury.56 The physical signs of inflammation in OAB in the absence of UTI have been suggested by biopsy studies.57 Inflammation in the bladder typically involves lymphocytic mononuclear predominance restricted to the upper layers of the bladder wall, especially the sub-urothelium.58 Recent studies have shown that bladder inflammation induced by infiltrated immune cells can be further amplified by the resident cells of urothelium and detrusor through the release of chemoattractants called chemokines, such as MCP-1 and IL-8.