Chronic changes in the brain Mg2+ concentration after forebrain ischemia in the rat.
Brain Mg2+ ion concentrations, [Mg2+], were evaluated in three groups of animals subjected to either 8 minutes (n = 10), or 12 minutes (n = 10) of near-complete forebrain ischemia, or sham operation (n = 10), from their 31P NMR spectra. No significant differences were observed in [Mg2+] among sham operated animals prior to or at any time point after surgery. In the 8-min ischemia group, mean [Mg2+] were significantly lower at 48 (0.28 +/- 0.06 mM, p = 0.014) and 72 (0.29 +/- 0.07 mM, p = 0.005) hours post-ischemia when compared to their mean pre-ischemia levels (0.39 +/- 0.08 mM). [Mg2+] was restored to pre-ischemia values at 96 hours after induction of ischemia. In the 12 min ischemia group, [Mg2+] were lower at all time points post-ischemia when compared to their pre-ischemia levels. Our data shows that forebrain ischemia causes a chronic decline of cerebral Mg2+ concentration, and the observed reduction of this cation can be partially attributed to concurrent brain tissue alkalosis.
Vande Linde
A M
AM
Department of Neurology, Henry Ford Health Sciences Center, Detroit, MI.
Chopp
M
M
Chen
H
H
Helpern
J A
JA
Knight
R
R
Schultz
L
L
Welch
K M
KM
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D016548:Prosencephalon / Q000098:blood supply; D051381:Rats; D011919:Rats, Inbred Strains
D008274:Magnesium