Effects of myocardial ischemia on cardiac contractility and ion transport in working and Langendorff rabbit heart.
In order to define the ischemic myocardial injury in terms of the possible alteration of cardiac membrane properties, Rb+ uptake and 3H-ouabain binding to cardiac tissue were compared in normal and ischemic rabbit hearts. In isolated Langendorff or working rabbit hearts, a global ischemia was produced by reducing the coronary flow of oxygenated Krebs-Henseleit solution for various time intervals. The normal or ischemic tissues were subjected to study the uptake of Rb+ and ouabain bindings. In Langendorff hearts there was little or no significant difference in active uptake of Rb+ in normal and ischemic heart. However, in the working heart, there was a significant decrease in Rb+ uptake in the ischemic hearts. As the case of Rb+ uptake ouabain binding was significantly reduced in ischemic working heart in comparison to working normal heart preparations at high concentrations of ouabain, the present study suggests the importance of cardiac contractility for the cellular energy metabolism and membrane transport activity.
D000818:Animals; D001693:Biological Transport, Active; D003327:Coronary Disease / Q000503:physiopathology*; D005260:Female; D066298:In Vitro Techniques; D007477:Ions; D008297:Male; D009200:Myocardial Contraction; D010042:Ouabain / Q000378:metabolism; D010477:Perfusion; D011817:Rabbits; D012413:Rubidium / Q000378:metabolism
D007477:Ions; D010042:Ouabain; D012413:Rubidium