Introduction: 

In the last two decades we reported on various kinds (uniform, regular or not, burst-like) of vesical (and pyeloureteral) motor and electrical patterns [Proc. IUPS 17 (Helsinki) 529/1989; 18 (Glasgow) 140.31&140.32/ 1993; 21 (San Diego) Faseb J., 19/4, A585/2005]. Presently will be informed on their K-dependence.

Method: 

Motor (isometric), electrical (intracellular-recording) vesical-activity (guinea-pig).

Results: 

Spontaneous phasic detrusor-contractions (SPC): Detrusor-amplitudes (4.1 ± 2.4 mN=100%) increased after 3 ( KCl (normal 5.6 mM=1(, McEwen-solution) 354% (at 3 mN) resp. 467% (50 mN stretch), frequency was unchanged (4.0 ± 0.7/ min=100%). Tonic trigonum-contractions (STC): Amplitudes (17.2 ± 11.6 mN) were unchanged after 3 ( KCl, but frequency (0.3 ± 0.1/min=100%) increased to 198% (3mN)/764% (50 mN). K-effect on electrical action potentials of vesical myocytes: Not only spike (S) activity was transformed into a burst-plateau (BP) one by stretch (3 to 80 mN), but also 2-5( [KCl] induced BP with decreased duration and increased frequency (proportionally to [KCl]). The K-phenomena appeared also in whole bladder preparations in vitro and in toto (isovolumetric cystotonometry) (total n = 60).

Conclusion: 

Various kinds of electrical and motor detrusor patterns are related probably to stretch-dependent K-channels, also to gap-junctions (intercellular excitation-conduction) [Eur. J. Physiol. 443, S334/2002; 430, 163/1995; 420, R99/1992; 419, R98/1991; Br. J. Urol. 94/2, 258/9/2004; Urol. 68/5A, 78-9/2006]. Further investigations could open new possibilities for a vesical pharmacological and electrotherapy (incontinence, overactive-bladder, etc.).