Attenuation of ischemia-induced regional myocardial acidosis by LP-805, a newly developed vasodilator, in dogs.
The effect of 8-tert-butyl-6,7-dihydropyrrolo[3,2-e]-5-methyl- pyrazolo[1,5-a]pyrimidine-3-carbonitrile (LP-805), a newly developed vasodilator, on myocardial acidosis induced by ischemia was studied in anesthetized open-chest dogs. Ischemia was induced by partially occluding the left anterior descending coronary artery. The coronary flow was artificially reduced to about 1/3 of the original flow. Myocardial pH was measured with a glass micro pH electrode inserted into the left ventricular wall perfused by the occluded artery. Myocardial pH decreased from about 7.5 to about 6.9 after the onset of ischemia and remained at this low level until the occluded coronary artery was released. After 30 min of ischemia, either saline containing 0.1 N HCl or 10, 30 or 100 micrograms/kg of LP-805 was injected intravenously. LP-805 attenuated the decrease in myocardial pH induced by ischemia in a dose-dependent manner. In conclusion, LP-805 may reduce the influence of ischemia on the myocardium.
Ichihara
K
K
Department of Pharmacology, Asahikawa Medical College, Japan.
Morimoto
T
T
Shiba
T
T
Tsujitani
M
M
Abiko
Y
Y
D000138:Acidosis / Q000188:drug therapy* / Q000209:etiology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000150:complications*; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D011720:Pyrazoles / Q000627:therapeutic use*; D011743:Pyrimidines / Q000627:therapeutic use*; D014665:Vasodilator Agents / Q000627:therapeutic use*
D011720:Pyrazoles; D011743:Pyrimidines; D014665:Vasodilator Agents; C073993:8-tert-butyl-6,7-dihydropyrrolo(3,2-e)-5-methylpyrazolo(1,5-a)pyrimidine-3-carbonitrile