The wave phenomena in smooth muscle syncytia.

Based on the concept of a functional unit, a mathematical model of a segment of the gut is developed. The model comprises real anatomical, histomorphological, physiological, and pharmacological information on the function of the organ. Numerical investigation into the dynamics of the electromechanical wave phenomenon reveals the fundamental principles of wave initiation, formation, and propagation along electrically anisotropic longitudinal and isotropic circular smooth muscle syncytia. A pattern of self-sustained electrical activity with the formation of spiral waves is discovered in the longitudinal syncytia and is attributed to the change in conductivity in the syncytia as a result of mechanical deformation of smooth muscle fibers. The model adequately predicts the effects of pharmacological interventions on the dynamics of myoelectrical activity. Although no direct experimental comparison to the theoretical findings is possible at this stage, the proposed mathematical model provides new insight onto the basics of physiological processes--slow wave activity, electromechanical conjugation, etc.--and a clinical entity--gastrointestinal dysrhythmias.