[Effects of oxyphenamone on myocardial ischemia in cats and rats].
OBJECTIVE
To study the therapeutic effects of oxyphenamone, a novel inodilator, on myocardial ischemia.


METHODS
The cardiac hemodynamic variables in cats with acute myocardial infarction induced by occlusion of the left anterior descending coronary artery (LAD) were recorded with a physiological polygraph and electromagnetic flowmeter. A model of myocardial necrosis induced by subcutaneous injection of isoproterenol was used for evaluating the effects of drugs on myocardial enzymes and morphological change.


RESULTS
Intravenous injection of oxyphenamone (2 - 8 mg x kg(-1)) dose-dependently decreased heart rate, mean arterial pressure, vascular resistance and the parameters of myocardial oxygen consumption (tension time index, TTI) in cats with myocardial infarction. It increased myocardial contractile force and cardiac output transiently but showed no influence on the left ventricular pressure and cardiac work. The changes of myocardial morphology, creatine phosphate kinase (CPK), malodialdehyde (MDA) and serum glutamic-oxaloacetic transaminase (GOT) induced by isoproterenol in rats were diminished by intraperitoneal injection of oxyphenamone (4 - 8 mg x kg(-1)).


CONCLUSIONS
By the examination of the cardiac hemodynamics, myocardial enzymes and morphology, it showed that the myocardial damage induced by ischemia or beta-agonist can be antagonized markedly by oxyphenamone, indicating that oxyphenamone may be beneficial for the treatment of myocardial infarction.
Fan
Li-li
LL
Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China. fanlili@public3.bta.net.cn
Ma
Jun
J
Wang
Ya-fang
YF
Ruan
Ying-mao
YM
Zeng
Xian-ke
XK
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology; D002415:Cats; D006321:Heart / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D009930:Organic Chemicals / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology
D002316:Cardiotonic Agents; D009930:Organic Chemicals; D014665:Vasodilator Agents; C442156:oxyphenamone