Exogenously Administered Opioids Contract the Female Rat Intrinsic Urethral Sphincter In Vivo
(2010) In Neurourology and Urodynamics 29(5). p.777-782- Abstract
- Background and objective: Previous studies have reported immunoreactive opioid nerve fibers in the detrusor and lower urinary tract sphincters. However, there is a paucity of in vivo studies demonstrating the direct effect of endogenous opioids in these structures. In the present study, we investigated the contractile actions of intra-arterially administered exogenous Dynorphin-A, Met-enkephalin, Leu-enkephalin, morphine, and the opioid antagonist naltrexone on the female rat intrinsic urethral sphincter in vivo. Methods: Intraurethral pressure was recorded by a catheter placed at the maximum pressure zone of the intrinsic urethral sphincter in anesthetized female Sprague-Dawley rats. The effects of different opioids were studied and... (More)
- Background and objective: Previous studies have reported immunoreactive opioid nerve fibers in the detrusor and lower urinary tract sphincters. However, there is a paucity of in vivo studies demonstrating the direct effect of endogenous opioids in these structures. In the present study, we investigated the contractile actions of intra-arterially administered exogenous Dynorphin-A, Met-enkephalin, Leu-enkephalin, morphine, and the opioid antagonist naltrexone on the female rat intrinsic urethral sphincter in vivo. Methods: Intraurethral pressure was recorded by a catheter placed at the maximum pressure zone of the intrinsic urethral sphincter in anesthetized female Sprague-Dawley rats. The effects of different opioids were studied and expressed as means and as percentages of pressure change (cmH(2)O) of the baseline intraurethral pressure. Results: Dynorphin-A, Met-enkephalin, and Leu-enkephalin evoked rapid, long-lasting contractile effects on the female rat urethra. The greatest intraurethral pressure increase was evoked by Dynorphin-A (89.2 +/- 15.3%). For Met-enkephalin, intraurethral pressure increased by 70.2 +/- 21.8% and for Leu-enkephalin, the pressure increase was 60.6 +/- 20%. Morphine, however, evoked inconsistent intraurethral pressure changes, increasing the urethral pressure in three subjects and lowering the pressure in the remaining six subjects. The opioid antagonist naltrexone reduced the intraurethral pressure by a mean of -19.0 +/- 5.8%. Conclusion: Results of the present study suggest that endogenous opioids by their contractile action on the intrinsic urethral sphincter may play a role in the control of continence in rats, additional to cholinergic and noradrenergic pathways. Neurourol. Urodynam. 29:777-782, 2010. (C) 2010 Wiley-Liss, Inc. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1628794
- author
- Crayton, Robert ; Soller, Wolfgang LU ; Mattiasson, Anders LU ; Bossowska, Agnieszka ; Borkowski, Tomasz ; Majewski, Mariusz and Radziszewski, Piotr
- organization
- publishing date
- 2010
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- immunohistochemistry, intrinsic urethral sphincter, NANC, opioids
- in
- Neurourology and Urodynamics
- volume
- 29
- issue
- 5
- pages
- 777 - 782
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- wos:000279299700014
- scopus:77956814341
- pmid:19899147
- ISSN
- 0733-2467
- DOI
- 10.1002/nau.20822
- language
- English
- LU publication?
- yes
- id
- 214806a2-0061-4da5-8799-b5897356806b (old id 1628794)
- date added to LUP
- 2016-04-01 11:07:23
- date last changed
- 2022-01-26 05:38:50
@article{214806a2-0061-4da5-8799-b5897356806b,
abstract = {{Background and objective: Previous studies have reported immunoreactive opioid nerve fibers in the detrusor and lower urinary tract sphincters. However, there is a paucity of in vivo studies demonstrating the direct effect of endogenous opioids in these structures. In the present study, we investigated the contractile actions of intra-arterially administered exogenous Dynorphin-A, Met-enkephalin, Leu-enkephalin, morphine, and the opioid antagonist naltrexone on the female rat intrinsic urethral sphincter in vivo. Methods: Intraurethral pressure was recorded by a catheter placed at the maximum pressure zone of the intrinsic urethral sphincter in anesthetized female Sprague-Dawley rats. The effects of different opioids were studied and expressed as means and as percentages of pressure change (cmH(2)O) of the baseline intraurethral pressure. Results: Dynorphin-A, Met-enkephalin, and Leu-enkephalin evoked rapid, long-lasting contractile effects on the female rat urethra. The greatest intraurethral pressure increase was evoked by Dynorphin-A (89.2 +/- 15.3%). For Met-enkephalin, intraurethral pressure increased by 70.2 +/- 21.8% and for Leu-enkephalin, the pressure increase was 60.6 +/- 20%. Morphine, however, evoked inconsistent intraurethral pressure changes, increasing the urethral pressure in three subjects and lowering the pressure in the remaining six subjects. The opioid antagonist naltrexone reduced the intraurethral pressure by a mean of -19.0 +/- 5.8%. Conclusion: Results of the present study suggest that endogenous opioids by their contractile action on the intrinsic urethral sphincter may play a role in the control of continence in rats, additional to cholinergic and noradrenergic pathways. Neurourol. Urodynam. 29:777-782, 2010. (C) 2010 Wiley-Liss, Inc.}},
author = {{Crayton, Robert and Soller, Wolfgang and Mattiasson, Anders and Bossowska, Agnieszka and Borkowski, Tomasz and Majewski, Mariusz and Radziszewski, Piotr}},
issn = {{0733-2467}},
keywords = {{immunohistochemistry; intrinsic urethral sphincter; NANC; opioids}},
language = {{eng}},
number = {{5}},
pages = {{777--782}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Neurourology and Urodynamics}},
title = {{Exogenously Administered Opioids Contract the Female Rat Intrinsic Urethral Sphincter In Vivo}},
url = {{http://dx.doi.org/10.1002/nau.20822}},
doi = {{10.1002/nau.20822}},
volume = {{29}},
year = {{2010}},
}