Changes in urethral smooth muscle and external urethral sphincter function with age in rats
Takuma Oshiro1, Ryu Kimura1, Keiichiro Izumi1
1Department of Urology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan.
Physiological Reports
|December 28, 2020
Summary
Aging impairs urethral function, causing increased residual urine and reduced urethral perfusion pressure (UPP) in older rats. This study reveals age-related changes in the external urethral sphincter (EUS) and potential bladder-urethra dyscoordination.
Area of Science:
- Urology
- Gerontology
- Physiology
Background:
- Aging is associated with lower urinary tract symptoms.
- Urethral function and its age-related changes are not fully understood.
Purpose of the Study:
- To investigate age-related changes in urethral activity and external urethral sphincter (EUS) function in female rats.
Main Methods:
- Recorded intravesical pressure, urethral perfusion pressure (UPP), and EUS electromyography (EUS-EMG) in young, middle-aged, and aged rats.
- Performed continuous cystometry and analyzed EUS morphology.
Main Results:
- Increased residual urine volume in middle-aged and aged rats compared to young rats.
- Reduced UPP and EUS high-frequency oscillations in older rats.
- EUS atrophy and unclear voiding phases observed in aged rats.
Conclusions:
- Aging induces urethral smooth muscle and EUS dysfunction.
- These changes may lead to bladder-urethra dyscoordination and impact bladder voiding efficiency.
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