Bladder inhibition or excitation by electrical perianal stimulation in a cat model of chronic spinal cord injury
Article first published online: 24 OCT 2008
© 2008 THE AUTHORS. JOURNAL COMPILATION © 2008 BJU INTERNATIONAL
Volume 103, Issue 4, pages 530–536, February 2009
How to Cite
Wang, J., Liu, H., Shen, B., Roppolo, J. R., De Groat, W. C. and Tai, C. (2009), Bladder inhibition or excitation by electrical perianal stimulation in a cat model of chronic spinal cord injury. BJU International, 103: 530–536. doi: 10.1111/j.1464-410X.2008.08029.x
- Issue published online: 2 FEB 2009
- Article first published online: 24 OCT 2008
- Accepted for publication 18 June 2008
- perianal skin;
- electrical stimulation;
- spinal cord injury;
To test the hypothesis that perianal electrical stimulation (PES) in chronic spinal cord-injured (SCI) cats could induce frequency-dependent inhibitory or excitatory reflex bladder responses.
MATERIALS AND METHODS
The experiments were conducted ≥4–5 weeks after spinal cord transection at the T9-T10 level. PES was applied via a pair of hook electrodes to the perianal skin area in three awake female cats with chronic SCI. A double-lumen balloon catheter was inserted through the urethra into the bladder to monitor bladder pressure and infuse saline (2–4 mL/min).
Under isovolumetric conditions PES at 3–10 Hz significantly inhibited large-amplitude reflex bladder activity induced by bladder distension above the micturition volume threshold. However, PES at 20–50 Hz induced large-amplitude bladder contractions when the bladder volume was below the micturition volume threshold. Inhibitory PES (7 Hz) significantly increased the mean (sem) bladder capacity by 40 (10)% when it was applied continuously during cystometrography. The optimum excitatory PES (30 Hz) induced large-amplitude (>25 cmH2O), long-duration (>20 s) bladder contractions at a wide range of bladder volumes (10–90% of bladder capacity).
This study showed that activation of pudendal afferent fibres by PES could induce frequency-dependent reflex bladder responses in awake cats with chronic SCI, indicating that a possible noninvasive treatment based on PES could be developed to restore both continence and micturition function for patients with SCI.