Hypothermic preservation of the rat heart. Comparison of immersion and low-flow perfusion methods: contribution of 31P-NMR spectroscopy.
Comparison of rat heart preservation by simple storage in a cardioplegic solution at 4 degrees C (6 hr for group I; 15 hr for group II) and by hypothermic low-flow perfusion of the same solution (0.3 ml min-1, 15 hr: group III) was performed by measuring biochemical and functional parameters and by collecting 31P-NMR spectroscopy data. When compared to control values, adenine nucleotide levels remained unchanged in group I hearts, while glycogen was 45% hydrolyzed and lactate level increased by 700%. Extension of heart immersion to 15 hr (group II) led to breakdown of ATP (-77%), of the sum of adenine nucleotides (-27%), and of glycogen (-77%), whereas lactate accumulation reached 900% of the control value. Functional recovery, measured at the end of a 60-min reperfusion was less than 10% in group II hearts when compared to group I hearts. This dramatic development was completely avoided by hypothermic low-flow perfusion (group III). 31P-NMR data showed that phosphocreatine was completely degraded in all groups of preserved hearts. Low-flow perfusion limited cellular acidosis. The ATP/Pi (Pi = inorganic phosphate) ratio calculated from NMR data was lower for group II hearts (0.04 +/- 0.01, n = 6) than for group I hearts (0.29 +/- 0.12; n = 6) or group III hearts (0.19 +/- 0.09; n = 6) and could constitute a convenient bioenergetic index to predict the capability of the heart to recover satisfactory contractility following a preservation period.
Centre Regional de Transfusion Sanguine, Lyon, France.
A
A
Larese
J
J
Aussedat
A
A
Ray
P
P
Marcsek
S
S
Lortet
G
G
Dureau
A
A
Rossi
D000227:Adenine Nucleotides / Q000378:metabolism; D000818:Animals; D001834:Body Water / Q000378:metabolism; D002314:Cardioplegic Solutions; D015925:Cryopreservation / Q000379:methods*; D004734:Energy Metabolism; D005260:Female; D006003:Glycogen / Q000378:metabolism; D006321:Heart; D016027:Heart Transplantation; D007101:Immersion; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D009682:Magnetic Resonance Spectroscopy; D009206:Myocardium / Q000378:metabolism; D009926:Organ Preservation / Q000379:methods*; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains
D000227:Adenine Nucleotides; D002314:Cardioplegic Solutions; D007773:Lactates; D019344:Lactic Acid; D006003:Glycogen