Biomaterial Database

Energy metabolism, intracellular Na+ and contractile function in isolated pig and rat hearts during cardioplegic ischemia and reperfusion: 23Na- and 31P-NMR studies. 1995

V V Kupriyanov, and B Xiang, and K W Butler, and M St-Jean, and R Deslauriers

Institute for Biodiagnostics, National Research Council of Canada, Winnipeg, MB.

The purpose of the study was to compare the role of Na ions in the damage caused by cardioplegic ischemia in fast (rat) and slow (pig) hearts. Changes in intracellular Na+ (Na+i), high energy phosphates, and contractile function were assessed during ischemia (36 degrees C) and reperfusion in KCl-arrested perfused hearts using 31P-NMR and shift reagent (DyTTHA3-)-aided 23Na-NMR spectroscopy. In the pig hearts the rates of decrease of phosphocreatine (PCr), ATP and intracellular pH (pHi) were 3-4 times slower than the rates observed in the rat hearts. In the pig hearts PCr was observable (approximately 10%) during first 80 min of the ischemic period (90 min). Comparable decreases in ATP (32.0 +/- 6 vs. 38 +/- 15% of initial) and pHi, (to 6.14 +/- 0.06 vs. 6.10 +/- 0.15) observed after 90 and 20 min ischemia in pig and rat hearts, respectively, were associated with a smaller Na+i increase in the pig hearts (to 175 +/- 31%) than in the rat hearts (to 368 +/- 62%). This Na+ increase in the rat hearts preceded development of ischemic contracture (41 +/- 6 mmHg at 23.6 +/- 0.7 min) while no contracture was observed in pig hearts. Reperfusion of the rat hearts (at 30 min ischemia) was followed by partial recovery of PCr (44 +/- 3%) and Na+i (234 +/- 69%) and poorer recovery of the pressure-rate product (PRP, 9 +/- 4%) and end-diastolic pressure (EDP, 72 +/- 5 mmHg) compared to the pig hearts (PCr, 106 +/- 25%; Na+i, 82 +/- 17%; PRP, 24 +/- 3%; EDP, 4.6 +/- 2.5 mmHg). The loss of function in the pig hearts was reversed by increasing Ca++ in the perfusate from 1 to 2.3 mM and resulted in a rise in both PRP and oxygen consumption rate, V(O2), from 24 +/- 3.3 to 64.5 +/- 5.8% and from 55 +/- 10 to 74 +/- 10% of the control levels, respectively. The PRP/delta V(O2) ratio was halved in the post-ischemic pig hearts and returned to the pre-ischemic level following Ca++ stimulation. It is suggested that the higher stability of Na+ homeostasis to ischemic stress in the pig heart may result from: 1) a lower ratio of the rate of ATP hydrolysis to glycolytic ATP production; 2) differences in the kinetic properties of the Na+ transporters. Reduced Na+ accumulation during ischemia and reperfusion is beneficial for metabolic and functional preservation of cardiomyocytes.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009200	Myocardial Contraction	Contractile activity of the MYOCARDIUM.	Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D009682	Magnetic Resonance Spectroscopy	Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).	In Vivo NMR Spectroscopy,MR Spectroscopy,Magnetic Resonance,NMR Spectroscopy,NMR Spectroscopy, In Vivo,Nuclear Magnetic Resonance,Spectroscopy, Magnetic Resonance,Spectroscopy, NMR,Spectroscopy, Nuclear Magnetic Resonance,Magnetic Resonance Spectroscopies,Magnetic Resonance, Nuclear,NMR Spectroscopies,Resonance Spectroscopy, Magnetic,Resonance, Magnetic,Resonance, Nuclear Magnetic,Spectroscopies, NMR,Spectroscopy, MR
D010710	Phosphates	Inorganic salts of phosphoric acid.	Inorganic Phosphate,Phosphates, Inorganic,Inorganic Phosphates,Orthophosphate,Phosphate,Phosphate, Inorganic
D010725	Phosphocreatine	An endogenous substance found mainly in skeletal muscle of vertebrates. It has been tried in the treatment of cardiac disorders and has been added to cardioplegic solutions. (Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Englewood, CO, 1996)	Creatine Phosphate,Neoton,Phosphocreatine, Disodium Salt,Phosphorylcreatine,Disodium Salt Phosphocreatine,Phosphate, Creatine
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog