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Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Intraurethral stimulation for reflex bladder activation depends on stimulation pattern and location.
Tim M Bruns1, Narendra Bhadra, Kenneth J Gustafson
1Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA. tmb30@case.edu
Neurourology and Urodynamics
|March 5, 2009
Summary
Investigating urethral stimulation in cats revealed distinct pathways for bladder control. Different frequencies and locations activate specific neural circuits, informing neuroprosthetic device development for bladder function.
Area of Science:
- Neuroscience
- Urology
- Biomedical Engineering
Background:
- Reflex bladder excitation is achievable via pudendal nerve stimulation, but parameters and anatomical correlations remain unclear.
- Understanding lower urinary tract neurophysiology is crucial for advancing human studies and neuroprosthetic development.
Purpose of the Study:
- To investigate the relationship between urethral anatomical locations and bladder excitability.
- To determine optimal stimulation parameters for reflex bladder activation.
Main Methods:
- Intraurethral stimulation was performed in nine cats at near isovolumetric bladder volumes.
- Bladder excitability was assessed using low (2 Hz) and high (33 Hz) frequency stimuli along the urethra before and after spinalization.
Main Results:
- High-frequency stimuli were effective at all urethral locations pre-spinalization, but only in the mid and distal urethra post-spinalization.
- Low-frequency stimuli were effective in the proximal and mid urethra pre-spinalization, but not post-spinalization.
- Bursting pulse stimulation patterns generally produced greater bladder pressures than continuous frequencies.
Conclusions:
- Two distinct urethral pathways for reflex bladder activation were identified: a supra-T10 circuit (proximal/mid urethra, low/high frequency) and a sacral circuit (mid/distal urethra, high frequency).
- Findings suggest potential anatomical targets and stimulus patterns for clinical neuroprostheses aimed at bladder control.
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