title: Connexin 43 and ischemic preconditioning.
abstract: Connexin 43 (Cx43) is the essential protein to form hemichannels and gap junctions in the myocardium. The phosphorylation status of Cx43 which is regulated by a variety of protein kinases and phosphatases determines hemichannel and/or gap junction conductance and permeability. Gap junctions are involved in cell-cell coupling while hemichannels contribute to cardiomyocyte volume regulation. Cx43-formed channels are involved in ischemia/reperfusion injury, since blockade of a large portion of Cx43-formed channels attenuates ischemic hypercontracture, infarct development and post myocardial infarction remodeling. Ischemic preconditioning's protection also depends on functional Cx43-formed channels, since uncoupling of channels or genetic Cx43 deficiency abolishes infarct size reduction by ischemic preconditioning. The exact underlying mechanism(s) how Cx43 mediates protection remain to be established.
authors.affiliation: Institut für Pathophysiologie, Zentrum für Innere Medizin, Universitätsklinikum Essen, Hufelandstrasse 55, 45122 Essen, Germany. rainer_schulz@uni-essen.de
authors.forename: Rainer
authors.initials: R
authors.lastname: Schulz
authors.forename: Gerd
authors.initials: G
authors.lastname: Heusch
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002463:Cell Membrane Permeability; D018031:Connexin 43 / Q000378:metabolism*; D017629:Gap Junctions / Q000378:metabolism*; D006801:Humans; D007473:Ion Channels / Q000378:metabolism*; D019157:Ischemic Preconditioning, Myocardial; D015428:Myocardial Reperfusion Injury / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*
chemical_list: D018031:Connexin 43; D007473:Ion Channels