Urological Science

REVIEW ARTICLE
Year
: 2022  |  Volume : 33  |  Issue : 3  |  Page : 101--113

Current knowledge and novel frontiers in lower urinary tract dysfunction after spinal cord injury: Basic research perspectives


Naoki Wada1, Sergei Karnup2, Katsumi Kadekawa4, Nobutaka Shimizu4, Joonbeom Kwon4, Takahiro Shimizu4, Daisuke Gotoh4, Hidehiro Kakizaki4, William C de Groat2, Naoki Yoshimura3 
1 Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Japan
2 Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
3 Department of Urology; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA

Correspondence Address:
Naoki Wada
Department of Urology, University of Pittsburgh School of Medicine, Suite 700, Kaufmann Medical Bldg, 3471 Fifth Ave, Pittsburgh, PA 15213

This review article aims to summarize the recent advancement in basic research on lower urinary tract dysfunction (LUTD) following spinal cord injury (SCI) above the sacral level. We particularly focused on the neurophysiologic mechanisms controlling the lower urinary tract (LUT) function and the SCI-induced changes in micturition control in animal models of SCI. The LUT has two main functions, the storage and voiding of urine, that are regulated by a complex neural control system. This neural system coordinates the activity of two functional units in the LUT: the urinary bladder and an outlet including bladder neck, urethra, and striated muscles of the pelvic floor. During the storage phase, the outlet is closed and the bladder is quiescent to maintain a low intravesical pressure and continence, and during the voiding phase, the outlet relaxes and the bladder contracts to promote efficient release of urine. SCI impairs voluntary control of voiding as well as the normal reflex pathways that coordinate bladder and sphincter function. Following SCI, the bladder is initially areflexic but then becomes hyperreflexic due to the emergence of a spinal micturition reflex pathway. However, the bladder does not empty efficiently because coordination between the bladder and urethral sphincter is lost. In animal models of SCI, hyperexcitability of silent C-fiber bladder afferents is a major pathophysiological basis of neurogenic LUTD, especially detrusor overactivity. Reflex plasticity is associated with changes in the properties of neuropeptides, neurotrophic factors, or chemical receptors of afferent neurons. Not only C-fiber but also Aδ-fiber could be involved in the emergence of neurogenic LUTD such as detrusor sphincter dyssynergia following SCI. Animal research using disease models helps us to detect the different contributing factors for LUTD due to SCI and to find potential targets for new treatments.


How to cite this article:
Wada N, Karnup S, Kadekawa K, Shimizu N, Kwon J, Shimizu T, Gotoh D, Kakizaki H, de Groat WC, Yoshimura N. Current knowledge and novel frontiers in lower urinary tract dysfunction after spinal cord injury: Basic research perspectives.Urol Sci 2022;33:101-113


How to cite this URL:
Wada N, Karnup S, Kadekawa K, Shimizu N, Kwon J, Shimizu T, Gotoh D, Kakizaki H, de Groat WC, Yoshimura N. Current knowledge and novel frontiers in lower urinary tract dysfunction after spinal cord injury: Basic research perspectives. Urol Sci [serial online] 2022 [cited 2022 Sep 29 ];33:101-113
Available from: https://www.e-urol-sci.com/article.asp?issn=1879-5226;year=2022;volume=33;issue=3;spage=101;epage=113;aulast=Wada;type=0