title: Connexins and the atrioventricular node.
abstract: The structure and functioning of the atrioventricular (AV) node has remained mysterious owing to its high degree of complexity. In this review article, we integrate advances in knowledge regarding connexin expression in the AV node. Complex patterning of 4 different connexin isoforms with single channel conductances ranging from ultralow to high explains the dual pathway electrophysiology of the AV node, the presence of 2 nodal extensions, longitudinal dissociation in the penetrating bundle, and, most importantly, how the AV node maintains slow conduction between the atria and the ventricles. It is shown that the complex patterning of connexins is the consequence of the embryonic development of the cardiac conduction system. Finally, it is argued that connexin dysregulation may be responsible for AV node dysfunction.
authors.affiliation: Institute of Cardiovascular Sciences, University of Manchester, Core Technology Facility, 46 Grafton St, Manchester, UK.
authors.forename: Ian P
authors.initials: IP
authors.lastname: Temple
authors.forename: Shin
authors.initials: S
authors.lastname: Inada
authors.forename: Halina
authors.initials: H
authors.lastname: Dobrzynski
authors.forename: Mark R
authors.initials: MR
authors.lastname: Boyett
mesh_terms: D000818:Animals; D001283:Atrioventricular Node / Q000378:metabolism* / Q000502:physiology; D054849:Cardiac Electrophysiology; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D006325:Heart Atria / Q000473:pathology / Q000503:physiopathology; D006329:Heart Conduction System / Q000378:metabolism* / Q000502:physiology; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D011817:Rabbits; D012680:Sensitivity and Specificity; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis / Q000503:physiopathology
chemical_list: D017630:Connexins