Smooth muscle electromyography of the urinary bladder

✍ Scribed by J.R. Scheepe; G. Wipfler; S. Schumacher; S. Bross; S. Zendler; K.-P. Jünemann; P. Alken

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 134 KB
• Volume: 17
• Category: Article
• ISSN: 0733-2467
• DOI: 10.1002/(sici)1520-6777(1998)17:1<71::aid-nau9>3.0.co;2-a

✦ Synopsis

To elucidate smooth muscle activity of the urinary bladder, we utilized an optimized animal model and a specially developed, computer-aided data acquisition and analysis system for bioelectrical signals. Twenty-five Wistar rats were pharmacologically paralyzed and artificially respirated. The urinary bladder was exposed by a suprapubic midabdominal incision, and both ureters were ligated to prevent physiological filling of the bladder. The bladder was initially emptied by slight manual pressure and was then filled via a transurethral catheter in 0.1-ml steps to a maximum of 0.45 ml with physiological saline. A custom-made, gold-plated needle electrode was tangentially guided by a micromanipulator to the smooth muscle of the bladder dome, and the recordings commenced. Furthermore, smooth muscle EMG recordings of the bladder were performed after pharmaco-stimulation of the detrusor with carbachol. Initial results demonstrate that, with the animal model presented here, it is possible to record reproducible and almost artifact-free smooth muscle activity from the urinary bladder. All experiments displayed a stochastic distribution of similar electrical events, increasing in appearance and amplitude with increased bladder volume and after pharmacostimulation with carbachol. Two-dimensional power spectrum analysis revealed a main signal frequency below 1 Hz.