Improved energy preservation following gentle reperfusion after hypothermic, ischemic cardioplegia in infarcted rat hearts.
The influence of temperature and pressure during early reperfusion after 2 h of hypothermic, cardioplegic ischemia was investigated. Adenosine triphosphate (ATP) and creatine-phosphate (CP) were measured after 45-min reperfusion. The experiments were carried out in normal and previously infarcted rat hearts (the left coronary artery having been ligated 3 weeks earlier). Four groups, each containing six hearts, were studied. Group 1 consisted of normal hearts reperfused with an abrupt rise in temperature and pressure, group 2 of normal hearts exposed to slowly rising temperature and pressure, and group 3 and 4 of previously infarcted hearts. Reperfusion procedures in groups 3 and 4 were the same as in group 1 and 2, respectively. The study showed that previously infarcted hearts have a lowered tolerance to ischemia and that the reperfusion technique may influence the preservation of myocardial energetics, although this influence was not statistically significant in normal hearts following only 2 h of ischemia. The gently reperfused infarcted hearts had energy stores equal to the normal hearts after 2 h of ischemia and 45 min of reperfusion, whereas the infarcted hearts reperfused in a rougher mode had significantly lowered values (P less than 0.05 for ATP and P less than 0.01 for CP).
Gunnes
S
S
Department of Surgery, University of Tromsø, Norway.
Ytrehus
K
K
Sørlie
D
D
Helgesen
K G
KG
Mjøs
O D
OD
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004734:Energy Metabolism; D006324:Heart Arrest, Induced; D007036:Hypothermia, Induced; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism*; D015425:Myocardial Reperfusion; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control; D009206:Myocardium / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism; D011312:Pressure; D051381:Rats; D011919:Rats, Inbred Strains; D013696:Temperature
D010725:Phosphocreatine; D000255:Adenosine Triphosphate