Decrease in total and free magnesium concentration following traumatic brain injury in rats.
31P magnetic resonance spectroscopy was used to determine the intracellular free Mg2+ concentration prior to and following fluid percussion induced traumatic brain injury in rats. Prior to injury, cerebral intracellular free Mg2+ concentration in the rat was 0.93 +/- 0.19 mM (mean +/- SE; n = 5). Following injury, free Mg2+ in the injured cortex declined by 70% within the first hour, and did not recover over the next 3 hours. Total Mg2+ also declined by 10% over this time period; however, there were no changes in brain Na+ or tissue water content. Because of its primary role in cellular metabolism, the early decline in tissue Mg2+ following brain trauma may be a critical factor in the development of irreversible tissue injury.
Vink
R
R
Department of Neurology, University of California, San Francisco.
McIntosh
T K
TK
Demediuk
P
P
Faden
A I
AI
D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D001929:Brain Edema / Q000378:metabolism; D001930:Brain Injuries / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000032:analysis*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
D000255:Adenosine Triphosphate; D008274:Magnesium