Magnesium deficiency exacerbates brain injury and stroke mortality induced by alcohol:: A 31P-NMR in vivo study

Mimicking in rats the reduced level of dietary magnesium (Mg) intake, seen in present-day Western World populations, short-term (4 weeks) restriction of Mg intake (30-35% normal) resulted in a 40% loss in brain intracellular free Mg2+ ions ([Mg2+](i)) and significant rises in brain intracellular pH (pHi) and phosphocreatine ([PCr]) but no change in [ATP] or [Pi] as measured by P-31-NMR spectroscopy. Such Mg-deficient animals (serum Mg fell 65%), when given ED40 stroke doses of ethanol, anol, demonstrated a 100% stroke mortality. These findings indicate that: 1) moderate, short term Mg deficiency makes the brain vulnerable to hypoxic-lethal stroke insults induced by alcohol administration, and 2) brain [Mg2+](i) appears to play an important role in finely regulating brain pHi and [PCr]. (C) 1998 Elsevier Science Inc.