Role of cellular orientation in electrical coupling between gastrointestinal smooth muscle.
Electrical fields produced during depolarization as well as low resistance pathways through gap junctions have been proposed as electrical coupling mechanisms serving to coordinate electrical control activity in gastrointestinal smooth muscle. The differing orientations of the longitudinal and circular muscle layers offer many possible configurations for cells coupled by electrical fields. The boundary element method is used to investigate coupling, with respect to both gap junctions and field effects for ellipsoidal and cylindrical cells. Physiological considerations allow the possibility of aggregates of cells with coordinated electrical activity. The effect of multiple source cells on field coupling is also modeled. Results indicate that even small gap junctional conductances are effective for coupling of smooth muscle and that field coupling is most efficacious when the ellipsoidal cells are coupled side by side and when cylindrical cells are coupled end to end.
Vigmond
E J
EJ
Institute of Biomedical Engineering and Department of Electrical and Computer Engineering, University of Toronto, Ontario, Canada. vigmonde@igb.umontreal.ca
Bardakjian
B J
BJ
D000818:Animals; D001698:Biomedical Engineering; D004064:Digestive System / Q000166:cytology*; D004068:Digestive System Physiological Phenomena; D004594:Electrophysiology; D017629:Gap Junctions / Q000502:physiology; D006801:Humans; D008564:Membrane Potentials; D008954:Models, Biological; D009119:Muscle Contraction / Q000502:physiology; D009130:Muscle, Smooth / Q000166:cytology* / Q000502:physiology*