Successful treatment of acute myocardial ischaemia with teopranitol--a novel organic nitrate.
The present study was designed to examine the effects of a new organic nitrate, teopranitol, in acute myocardial ischaemia. Adult cats were subjected to 5 h of myocardial ischaemia by permanent ligation of the left anterior descending coronary artery (LAD). Teopranitol (10 mg kg-1 X h) or physiological saline (vehicle) was infused i.v., beginning 30 min after LAD occlusion and continued until the end of the experiment. All animals subjected to myocardial ischaemia showed a significant elevation of the ST-segment within 20 min of LAD occlusion. In the LAD-vehicle group, the ST-segment elevation continued to increase; teopranitol attenuated this increase and significantly reduced the ST-segment elevation at 4 and 5 h (P less than 0.05). The loss of creatine phosphokinase-specific activity from the ischaemic myocardium was significantly reduced by teopranitol (P less than 0.05), indicating an improved preservation of myocardial tissue. There was a significant initial reduction in mean arterial blood pressure by teopranitol in sham-operated cats but no consistent change of this parameter, heart rate or the computed pressure-rate product in LAD-occluded cats. Teopranitol did completely reverse the ischaemia induced formation of platelet aggregates at 1 to 5 h (P less than 0.05). It is concluded that teopranitol exerts a significant protective effect in acute myocardial ischaemia in vivo that is independent of changes in systemic haemodynamics and might be associated with the generation of an antiplatelet activity in vivo.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002415:Cats; D003327:Coronary Disease / Q000188:drug therapy*; D003331:Coronary Vessels; D003402:Creatine Kinase / Q000378:metabolism; D004562:Electrocardiography; D006339:Heart Rate / Q000187:drug effects; D008026:Ligation; D009206:Myocardium / Q000201:enzymology; D010976:Platelet Count / Q000187:drug effects; D013402:Sugar Alcohols / Q000627:therapeutic use*
D013402:Sugar Alcohols; C042286:teopranitol; D003402:Creatine Kinase