Myocardial high-energy phosphates, lactate and pyruvate during moderate or severe normothermic ischemia in rat hearts perfused with phosphoenolpyruvate and ATP in cardioplegic solution.
Rat hearts were subjected to normothermic ischemia for 15 min (group I) or 30 min (group II). During the ischemic period the hearts were perfused twice with cardioplegic solution supplemented with 14.4 mM phosphoenolpyruvate (PEP) and/or 0.067 mM adenosine triphosphate (ATP), and at the end of ischemia they were freeze-clamped. The myocardial ATP content in group I fell to about 55% of normal values except in hearts supplemented with only PEP, which showed greater reduction. In group II the ATP fell to only about 5% of normal values, without significant differences between the subgroups Hearts supplemented with PEP alone or with combined PEP-ATP showed significantly higher levels of pyruvate than in hearts with only ATP supplementation or control hearts. The study thus demonstrated clear difference in ATP content between moderate and severe ischemic trauma. The high pyruvate levels after PEP supplementation indicate formation of pyruvate without concomitant lactate increase.
Department of Thoracic and Cardiovascular Surgery, University Hospital, Uppsala, Sweden.
S
S
Thelin
J
J
Hultman
G
G
Ronquist
H E
HE
Hansson
D000227:Adenine Nucleotides / Q000378:metabolism*; D000818:Animals; D002314:Cardioplegic Solutions / Q000494:pharmacology; D003327:Coronary Disease / Q000378:metabolism*; D004734:Energy Metabolism; D007773:Lactates / Q000378:metabolism*; D009206:Myocardium / Q000032:analysis / Q000378:metabolism*; D010477:Perfusion; D010728:Phosphoenolpyruvate / Q000008:administration & dosage / Q000378:metabolism*; D051381:Rats; D013997:Time Factors
D000227:Adenine Nucleotides; D002314:Cardioplegic Solutions; D007773:Lactates; D010728:Phosphoenolpyruvate