Heart slice NMR.
Nuclear magnetic resonance (NMR) spectroscopy of the heart is normally carried out using whole heart preparations under coronary perfusion. In such preparations, either radical changes in ionic composition of the perfusate or applications of numerous drugs would affect coronary microcirculation. This report communicates the first (31)P NMR spectroscopy study using a heart slice preparation (left ventricular slices) superfused with extracellular medium. The ratio of phosphocreatine concentration to ATP concentration was approximately 2.1. Also, intracellular pH and Mg(2+) concentration ([Mg(2+)](i)), estimated from the chemical shifts of inorganic phosphate and ATP, were comparable with those under retrograde perfusion. [Mg(2+)](i) was significantly increased by the removal of extracellular Na(+), supporting the essential role of Na(+)-coupled Mg(2+) transport in Mg(2+) homeostasis of the heart. Heart slice preparation could also be used to evaluate the potency of cardiac drugs, regardless of their possible effects on coronary microcirculation.
Uetani
Tadayuki
T
Department of Cell Physiology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
Yamashita
Daisuke
D
Shimizu
Juichiro
J
Misawa
Hiromi
H
Tatematsu
Yasushi
Y
Hamaguchi
Yukihisa
Y
Miyasaka
Takehiro
T
Katanosaka
Yuki
Y
Kato
Toshiaki
T
Matsubara
Tatsuaki
T
Furukawa
Koichi
K
Murohara
Toyoaki
T
Takaki
Miyako
M
Nakayama
Shinsuke
S
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D017920:Antiporters / Q000378:metabolism*; D006352:Heart Ventricles / Q000378:metabolism; D016591:Histocytological Preparation Techniques; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007552:Isotonic Solutions; D008274:Magnesium / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009206:Myocardium / Q000378:metabolism*; D010477:Perfusion; D010725:Phosphocreatine / Q000378:metabolism; D017553:Phosphorus Compounds / Q000378:metabolism; D010759:Phosphorus Isotopes; D051381:Rats; D017208:Rats, Wistar
D017920:Antiporters; D007552:Isotonic Solutions; D017553:Phosphorus Compounds; D010759:Phosphorus Isotopes; C037692:Tyrode's solution; C046250:sodium-magnesium antiporter; D010725:Phosphocreatine; D000255:Adenosine Triphosphate; D008274:Magnesium