Introduction: 

Myometrial motor oscillations are fundamentals for parturition. Investigations demonstrate a probable relation between motor activity of myometrium, uterine artery, vesical trigone from surgical tissue (Abstract-Book-1, Int. Congr. Gyn. Kuala-Lumpur, 64/2006; Br. J. Urol. 94/2, 258-9/2004; Urol. 68/5A, 78-9/2006). Recent and earlier results support the possibility for a more effective treatment of pathological myometrial activity.

Method: 

Motor (isotonic) activity of preparations (see introd.).

Results: 

Human myometrium generates spontaneous slow tonic contractions (STC: 0.22 ± 0.01/min) with amplitudes of 30-5% (mean=12%) of prep. length (n = 101): STC can be transformed into spontaneous fast phasic contractions, similar to uterine tube (SPC: 0.65 ± 0.35/min), with small amplitudes (about 1-6%) by combined effects of hormones and drugs [1 nM – 10 mM: met-/leu-enkephalins, melatonine, cAMP, PGE1; herbal drugs, antihistaminics, phosophodiesterase inhibitors, ß-sympathomimetics, Ca⁺⁺-antagonists]. Hormones (adrenaline, 5-HT) induced STC in uterine artery. Human (and guinea pig, n = 40) trigone generated also STC (0.3 ± 0.1/min); detrusor SPC (3.8 ± 0.9/min) could be transformed into STC by TEA/BaCl₂. Anaesthetics (e.g. procaine): 0.1-10 mM inhibited STC/electro-induced contractions (10Hz, 0.3-40ms, 3s).

Conclusion: 

SPC/STC are probably related to electrical stretch-dependent spike/burst-plateau activities, similar to vesical myocytes (Eur. J. Physiol. 443S, 334/2002; Faseb J. 19/4, A585/2005). Systematic investigations of myometrial electro- (K-/Ca-stretch channels) and pharmaco-physiology could open new approaches for more effective (incl. tokolytic) therapy of abortus, partus pramaturus et serotinus, dysmenorrhoe, etc.