Functional and metabolic effects of cardioplegia induced by a young's solution (YNG solution) as assessed in isolated atrial preparations and in isolated perfused heart preparations of the guinea pig.
p6e protective effects of Young's solution (YNG solution), a cardioplegic solution, on the myocardial function and metabolism were assessed in isolated atrial preparations and isolated perfused heart preparations of the guinea pig. In atrial preparations, the time to arrest of the contraction became shorter as the concentrations of the K+, Mg++, and K+-Mg++ solutions increased, while the time to resumption of the contraction was lengthened. There was no difference in the time to arrest between K+ and K+-Mg++ solutions, but the time to resumption was reduced with K+-Mg++ solution to about half the value with K+ solution. YNG solution represented an optimum solution for obtaining a quick cardiac arrest and quick resumption of contraction. In the isolated perfused heart, the time to arrest was similar for all the cardioplegic solutions used and the heart stopped in diastole. However, the time to arrest was longer with cold Krebs-Henseleit's solution (cold cardioplegia). The time to resumption of the contraction was the shortest with YNG solution, which yielded the highest mitochondrial respiratory control ratio (RCR) and ADP/O ratio. There was a negative correlation between the time to resumption of contraction and mitochondrial RCR or ADP/O ratio (r = -0.50 and -0.58, respectively).
D000818:Animals; D002951:Citrates; D003326:Coronary Circulation / Q000187:drug effects*; D004338:Drug Combinations; D004341:Drug Evaluation; D006168:Guinea Pigs; D006324:Heart Arrest, Induced; D006325:Heart Atria / Q000187:drug effects* / Q000378:metabolism; D008278:Magnesium Sulfate; D008297:Male; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000378:metabolism; D009200:Myocardial Contraction / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism*; D009388:Neostigmine; D010101:Oxygen Consumption; D011188:Potassium; D019357:Potassium Citrate; D013997:Time Factors
D002951:Citrates; D004338:Drug Combinations; C042312:Young's cardioplegic solution; D009388:Neostigmine; D008278:Magnesium Sulfate; D019357:Potassium Citrate; D011188:Potassium