Dipyridamole-induced decrement of functional recovery of postischemic reperfused myocardium in conscious dogs with well-developed coronary collateral circulation.
The effects of dipyridamole (20 and 40 micrograms/kg/min intravenously) on the time course of functional recovery of myocardium after five 5-minute coronary artery occlusions and four 5-minute reperfusions and a subsequent 5-hour reperfusion period were studied in chronically instrumented, conscious dogs with well-developed coronary collateral circulation. In comparison with vehicle-treated control dogs, those given dipyridamole (20 and 40 micrograms/kg/min, respectively) 15 minutes before and during coronary occlusion had a greater depression of regional segment shortening (38 +/- 7% and 19 +/- 4%, respectively, vs control levels of 69 +/- 10% of preocclusion values) during acute coronary artery occlusion. After a 5-hour reperfusion period, segment shortening returned to preocclusion values in the control group but remained decreased in the dipyridamole groups (87 +/- 4% and 75%, respectively). These results suggest that dipyridamole in a dose-dependent manner exacerbates recovery of contractility of postischemic reperfused myocardium in dogs with well-developed coronary collateral circulation.
Kenny
D
D
Department of Anesthesiology, Medical College of Wisconsin, Milwaukee 53226.
Wynsen
J C
JC
Brooks
H L
HL
Warltier
D C
DC
D000818:Animals; D003097:Collateral Circulation / Q000502:physiology; D003326:Coronary Circulation / Q000502:physiology*; D003864:Depression, Chemical; D004176:Dipyridamole / Q000008:administration & dosage / Q000494:pharmacology*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D015425:Myocardial Reperfusion; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology*; D013997:Time Factors
D004176:Dipyridamole