Intracellular Electrical Activity in Human Urinary Bladder Smooth Muscle: The Effect of High Sucrose MediumVisser A.J. · van Mastrigt R.
Department of Urology-Urodynamics, Erasmus University Rotterdam, The Netherlands
Introduction: The primary key to pharmacotherapy of bladder instability is in the excitation-contraction coupling of detrusor smooth muscle cells. To study this process, simultaneous recordings of mechanical and electrical activity are required. However, recording of mechanical activity induces movement, which may affect the quality of intracellular recordings. Materials and Methods: We therefore compared the electrical activity of human detrusor smooth muscle cells in normal Krebs’ solution and in a hypertonic solution, which immobilizes the tissue, enabling us to study the effect of movement on the membrane potential. Carbachol and KCl were applied to induce contractions. Results: Sucrose in the medium made the tissue rigid and abolished its movement, while the electrical response was not affected. When compared with recordings in normal Krebs’ solution, the average resting membrane potential was not altered. However, the membrane potential was more stable, with far less spike-shaped potentials. The spike-shaped potential amplitude was larger, while the duration was decreased. Conclusions: Impairing the ability of tissue movement resulted in changes in the electrophysiological properties of detrusor smooth muscle cells. The results suggest that stretch has an effect on L-type Ca2+ channels.
© 2001 S. Karger AG, Basel
Received: Received: August 8, 2000
Accepted: November 23, 2000
Number of Print Pages : 7
Number of Figures : 4, Number of Tables : 1, Number of References : 30
Founded 1955 by G. Peter A. Narath and Heinrich Heusser; Continued 1968–1987 by G. Mayor
Vol. 66, No. 4, Year 2001 (Cover Date: Released May 2001)
Journal Editor: D. Hauri, Zürich; M.P. Wirth, Dresden
ISSN: 0042–1138 (print), 1423–0399 (Online)
For additional information: http://www.karger.com/journals/uin