title: The oxygen dependence of the energy state of cardiac tissue: 31P-NMR and optical measurement of myoglobin in perfused rat heart.
abstract: The relationship between the energy state and intracellular oxygen concentration was established with cardiac tissue, where the former could be monitored by 31P-NMR and the latter by optical method for myoglobin absorption. The ratio of creatinephosphate to inorganic phosphate, PCr/Pi, started to fall at higher intracellular oxygen concentration than oxygen consumption (10IM). The pH shift measured by frequency shift of Pi paralleled the increase of lactate-release, of which half maximum was approximately 3IM. The critical oxygen concentrations differed nearly 5-fold when determined by energy state and oxygen consumption.
authors.affiliation: Department of Cardiovascular Medicine, School of Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Fukuda
authors.forename: H
authors.initials: H
authors.lastname: Yasuda
authors.forename: S
authors.initials: S
authors.lastname: Shimokawa
authors.forename: M
authors.initials: M
authors.lastname: Tamura
mesh_terms: D000227:Adenine Nucleotides / Q000378:metabolism; D000818:Animals; D003576:Electron Transport Complex IV / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009211:Myoglobin / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010100:Oxygen / Q000032:analysis*; D010101:Oxygen Consumption; D010477:Perfusion; D010758:Phosphorus; D051381:Rats
chemical_list: D000227:Adenine Nucleotides; D009211:Myoglobin; C017595:oxymyoglobin; D009243:NAD; D010758:Phosphorus; D003576:Electron Transport Complex IV; D010100:Oxygen