Calculation of intracellular cerebral [Mg2+] during hypoxic ischemia by in vivo 31P NMR.
Several algorithms for the calculation of ionized intracellular magnesium concentration from the chemical shifts of MgATP were compared, using in vivo 31P NMR data obtained from swine brain during and following hypoxic ischemia plus i.v. MgSO4 infusion. This analysis reveals that both the absolute ionized intracellular magnesium and relative changes in magnesium may vary widely between algorithms used. The calculated intracellular pH, used in algorithms to determine ionized magnesium concentration was found to be a critical parameter that governs the extent of these differences.
Corbett
R J
RJ
Ralph Rogers and Mary Nell Magnetic Resonance Center, Department of Radiology, University of Texas Southwestern Medical Center at Dallas 75235-9085, USA.
Gee
J
J
Laptook
A R
AR
D000255:Adenosine Triphosphate / Q000378:metabolism; D000465:Algorithms; D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D002534:Hypoxia, Brain / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism*; D008278:Magnesium Sulfate / Q000493:pharmacokinetics; D009682:Magnetic Resonance Spectroscopy; D010710:Phosphates / Q000378:metabolism; D013552:Swine
D010710:Phosphates; D008278:Magnesium Sulfate; D000255:Adenosine Triphosphate; D008274:Magnesium