Effects of leukotriene D4 on myocardial blood flow and high energy phosphate concentration in anesthetized dogs.
The effects of intracoronary administration of leukotriene D4 (LTD4) on myocardial blood flow (MBF) and myocardial energy metabolism in anesthetized open-chest dogs were examined, and compared with those of coronary ligation. Two series of experiments were conducted. In the first, LTD4 (0-3.0 micrograms/kg) was injected into the left anterior descending coronary artery (LAD) and MBF was measured. While no changes in MBF were observed after 0.5 microgram/kg of LTD4, a significant decrease in MBF in the LAD area was apparent after 1.0 micrograms/kg of LTD4, with a return to baseline values by within 10 min after the injection. With 3.0 micrograms/kg of LTD4, MBF remained decreased up to 15 min after the injection. In the second study, myocardial high energy phosphate concentrations in the LAD area were determined 5 min after LTD4 administration and compared to those after ligation. ATP levels in the 1.0-3.0 micrograms/kg LTD4 groups were significantly less than those in the ligation group, although there were no associated significant differences in MBF values in the LAD area. These results indicate that LTD4 brings about changes in myocardial energy metabolism which are not secondary to reduced blood flow.
Third Department of Internal Medicine, Nagoya University School of Medicine, Japan.
T
T
Nishida
T
T
Matsubara
T
T
Kambe
N
N
Sakamoto
D000758:Anesthesia; D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects*; D003331:Coronary Vessels / Q000601:surgery; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism / Q000187:drug effects*; D005260:Female; D006339:Heart Rate; D017998:Leukotriene D4 / Q000494:pharmacology*; D008026:Ligation; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*
D010710:Phosphates; D017998:Leukotriene D4