TY - JOUR
T1 - Removal of urothelium affects bladder contractility and release of ATP but not release of NO in rat urinary bladder
AU - Munoz, Alvaro
AU - Gangitano, David A.
AU - Smith, Christopher P.
AU - Boone, Timothy B.
AU - Somogyi, George T.
N1 - Funding Information:
This work was supported by the National Institutes of Health (Grant RO1-DK-069988 to GTS) and the US Department of Veterans Affairs (CDA 200600158 to CPS). We would like to thank Prof. Gustavo Ayala M.D. for his help evaluating the microscopic pictures and Carolyn Schum medical editor for her work on the manuscript.
PY - 2010
Y1 - 2010
N2 - Background. The objective of our work was to investigate both the contractile function and the release of ATP and NO from strips of bladder tissue after removal of the urothelium. Methods. The method of removal was a gentle swabbing motion rather than a sharp surgical cutting to separate the urothelium from the smooth muscle. The contractile response and ATP and NO release were measured in intact as well as on swabbed preparations. The removal of the urothelial layer was affirmed microscopically. Results. After the swabbing, the smaller contractions were evoked by electrical as well as by chemical stimulation (50 M carbachol or 50 M , meATP). Electrical stimulation, carbachol and substance P (5 M) evoked lower release of ATP in the swabbed strips than in intact strips. Although release of NO evoked by electrical stimulation or substance P was not changed, release of NO evoked by carbachol was significantly less in the swabbed preparations. Conclusion. Since swabbing removes only the urothelium, the presence of the suburothelial layer may explain the difference between our findings and those of others who found an increase in contractility. Evoked release of ATP is reduced in swabbed strips, indicating that ATP derives solely from the urothelium. On the other hand, electrical stimulation and substance P evoke identical degrees of NO release in both intact and swabbed preparations, suggesting that NO can be released from the suburothelium. Conversely, carbachol-induced release of NO is lower in swabbed strips, implying that the cholinergic receptors (muscarinic or nicotinic) are located in the upper layer of the urothelium.
AB - Background. The objective of our work was to investigate both the contractile function and the release of ATP and NO from strips of bladder tissue after removal of the urothelium. Methods. The method of removal was a gentle swabbing motion rather than a sharp surgical cutting to separate the urothelium from the smooth muscle. The contractile response and ATP and NO release were measured in intact as well as on swabbed preparations. The removal of the urothelial layer was affirmed microscopically. Results. After the swabbing, the smaller contractions were evoked by electrical as well as by chemical stimulation (50 M carbachol or 50 M , meATP). Electrical stimulation, carbachol and substance P (5 M) evoked lower release of ATP in the swabbed strips than in intact strips. Although release of NO evoked by electrical stimulation or substance P was not changed, release of NO evoked by carbachol was significantly less in the swabbed preparations. Conclusion. Since swabbing removes only the urothelium, the presence of the suburothelial layer may explain the difference between our findings and those of others who found an increase in contractility. Evoked release of ATP is reduced in swabbed strips, indicating that ATP derives solely from the urothelium. On the other hand, electrical stimulation and substance P evoke identical degrees of NO release in both intact and swabbed preparations, suggesting that NO can be released from the suburothelium. Conversely, carbachol-induced release of NO is lower in swabbed strips, implying that the cholinergic receptors (muscarinic or nicotinic) are located in the upper layer of the urothelium.
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U2 - 10.1186/1471-2490-10-10
DO - 10.1186/1471-2490-10-10
M3 - Article
C2 - 20497558
AN - SCOPUS:77952496631
VL - 10
JO - BMC Urology
JF - BMC Urology
SN - 1471-2490
M1 - 10
ER -