Tzu Chi Medical Journal

ORIGINAL ARTICLE
Year
: 2020  |  Volume : 32  |  Issue : 1  |  Page : 26--29

The aging effects on phenylephrine-induced relaxation of bladder in mice


Chun-Kai Hsu1, Hsi-Hsien Chang1, Stephen Shei-Dei Yang2 
1 Division of Urology, Department of Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei, Taiwan
2 Division of Urology, Department of Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei; School of Medicine, Tzu Chi University, Hualien, Taiwan

Correspondence Address:
Dr. Stephen Shei-Dei Yang
Division of Urology, Department of Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, 289, Jian Guo Road, New Taipei
Taiwan

Objective: We have demonstrated that phenylephrine (PE) activates the capsaicin-sensitive nerves, and then activates capsaicin-sensitive nerves to release an unknown substance that facilitates the release of norepinephrine (NE) from adrenergic nerves. Subsequently, NE stimulates β-ARs in the detrusor muscle in mice, leading to neurogenic relaxation of the urinary bladder (UB). Materials and Methods: We examined if there existed sensory-motor dysfunction in UB of aging mice. To investigate the change of PE-induced detrusor relaxation in aging male-C57BL/6 mice (12- vs. 24-month-old mice), UB strips from mice were isolated, cut into strips, and mounted in the organ bath. Results: The UB strip contractility responding to various agents was estimated using tissue bath wire myography. Acetylcholine (ACh) and KCl-induced UB strips contraction was not significantly different between 24- and 12-month mice. NE-induced UB strips relaxation was significantly lower in 24-month than 12-month mice. Denuded bladder strips showed similar decreased relaxation response to NE. This NE-induced relaxation was inhibited by silodosin and lidocaine. PE did not induce contraction in UB strips of aging mice. In contrast, PE-induced relaxation was weaker in 24-month than 12-month mice. Conclusion: Our results suggested that the PE-induced relaxation was age related. Aging seemed to lead the sensory-motor dysfunction. More animal and human studies are required to prove this concept and its clinical usefulness in the future.


How to cite this article:
Hsu CK, Chang HH, Yang SS. The aging effects on phenylephrine-induced relaxation of bladder in mice.Tzu Chi Med J 2020;32:26-29


How to cite this URL:
Hsu CK, Chang HH, Yang SS. The aging effects on phenylephrine-induced relaxation of bladder in mice. Tzu Chi Med J [serial online] 2020 [cited 2020 Feb 17 ];32:26-29
Available from: http://www.tcmjmed.com/article.asp?issn=1016-3190;year=2020;volume=32;issue=1;spage=26;epage=29;aulast=Hsu;type=0