Reduction of size of myocardial infarction with nicorandil, a new antianginal drug, after coronary artery occlusion in dogs.
The effects of nicorandil, a new antianginal drug, on size of myocardial infarction were studied in anesthetized, open-chest dogs after left anterior descending coronary artery occlusion. To quantify the extent of the hypoperfused zone, 99mTc-albumin microspheres were injected into the left atrium 1 min after occlusion. Fifteen minutes after occlusion, dogs were randomly assigned to a control group or a nicorandil-treated group that received immediately after assignments 100 micrograms/kg of nicorandil followed by a continuous infusion of 30 micrograms/kg/min for 6 h. Six hours after occlusion, the left ventricle was cut into 3 mm thick slices for triphenyltetrazolium chloride staining and autoradiography. The extent of the hypoperfused zone (26.1% +/- 3.1% of the left ventricle in the control vs. 23.2% +/- 3.7% in the treated group, mean +/- SEM) was not different between the two groups. The ratio of the extent of myocardial necrosis to the extent of the hypoperfused zone was significantly smaller in the treated group (64.3% +/- 7.2%, n = 7, p less than 0.05) than in the control group (92.6% +/- 9.2%, n = 7). Thus, nicorandil administered early after coronary artery occlusion reduced the size of myocardial infarction by 31%.
Endo
T
T
First Department of Internal Medicine, Nippon Medical School, Japan.
Nejima
J
J
Kiuchi
K
K
Fujita
S
S
Kikuchi
K
K
Hayakawa
H
H
Okumura
H
H
D000818:Animals; D003327:Coronary Disease / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D004285:Dogs; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D009203:Myocardial Infarction / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000627:therapeutic use; D020108:Nicorandil; D014665:Vasodilator Agents / Q000627:therapeutic use*
D014665:Vasodilator Agents; D009536:Niacinamide; D020108:Nicorandil