Poster, Podium & Video Sessions
Presentation Authors: Kentaro Takezawa*, Makoto Kondo, Hiroshi Kiuchi, Norichika Ueda, Tetsuji Soda, Shinichiro Fukuhara, Tetsuya Takao, Yasushi Miyagawa, Akira Tsujimura, Kazumasa Matsumoto-Miyai, Yusuke Ishida, Suita, Japan, Hiromitsu Negoro, Kyoto, Japan, Shoichi Shimada, N
Introduction: Urothelial ATP signaling has been believed to have an essential role in micturition reflex. To clarify the exact role of urothelial ATP signaling in micturition reflex, we performed detailed in vivo functional analyses in purinergic receptor-deficient mice (Takezawa et al., Sci Rep, 2016).
Methods: Male C57BL/6J mice, P2X2-/-, and P2X3-/- mice were used. For the bladder functional analyses, the voided volume per micturition of free-moving mice was assessed by automated voided stain on paper method (Negoro et al., Nat commun, 2012), and the bladder capacity, post-voiding residual volume and intercontraction intervals were evaluated by mouse video-urodynamics testing (Takezawa et al., Am J Physiol Renal Physiol, 2014). (1) Bladder function under normal conditions was examined in wild-type (WT), P2X2-/-, and P2X3-/- mice. (2) Lipopolysaccharide (LPS)-induced changes of bladder function and increases in c-Fos-positive cells in the L6 spinal cord were analyzed in WT, P2X2-/-, and P2X3-/- mice.
Results: (1) Unexpectedly, a lack of P2X2 or P2X3 receptors did not affect bladder function under normal conditions (Figure 1). (2) In contrast, the LPS-induced bladder hyperactivity and an increase in c-Fos-positive cells in the L6 spinal cord were attenuated in P2X2-/-, and P2X3-/- mice (Figure 2).
Conclusions: These findings indicate that urothelial ATP signaling is not essential for normal micturition reflex under physiological conditions, but plays an important role in bladder hyperactivity under pathological conditions.
Source Of Funding: none
Kentaro Takezawa, M.D., Ph. D., Osaka University
2005 Bachelor of Medicine in Osaka University
2015 Ph. D. of Medicine in Osaka University
Urothelial ATP signaling: what is its role in bladder sensation? Neurourol Urodyn 2017
Authentic role of ATP signaling in micturition reflex. Sci Rep 2016
Combination of bladder ultrasonography and novel cystometry method in mice reveals rapid decrease in bladder capacity and compliance in LPS-induced cystitis. Am J Physiol Renal Physiol 2014
Tuesday, May 16
10:20 AM – 10:30 AM