title: [Magnesium in cerebrospinal fluid in acute cerebral ischemia: its relation to glutamate neurotoxicity].
abstract: BACKGROUND
  In animal models it has been shown that there is an increase in tissue magnesium concentration during cerebral ischemia. We studied the changes in magnesium levels in the cerebrospinal fluid (CSF) during the acute phase of cerebral ischemia.
  
  
  METHODS
  We included 95 patients with first ischemic cerebral infarcts admitted to hospital within the first 24 hours and also 37 controls. CT scan was done on admission and between four and seven days later (when the volume of the infarct was determined). The neurological defect was evaluated on the Canadian scale on admission, after 48 hours, on the seventh day and after three months. The CSF magnesium concentration was determined using a colorimetric method and the glutamate by HPLC.
  
  
  RESULTS
  The CSF magnesium concentrations were significantly higher in the patients than in the controls (2.6 +/- 0.6 mmol/l vs 2.2 +/- 0.6 mmol/l p = 0.0001). The magnesium concentration was higher in the larger infarcts (Pearson's coefficient = 0.2901, p = 0.0043), and in those presenting greater neurological defects after 48 hours (Spearman's coefficient = -0.4649, p < 0.0001). The magnesium concentration was not related to the presence of early signs on the initial CT scan and the Canadian scale rating on admission. The concentration of magnesium was significantly correlated with that of glutamate (Pearson coefficient = 0.7735, p < 0.0001).
  
  
  CONCLUSIONS
  The levels of magnesium in the CSF were satisfactorily related to the volumes of the infarct and the intensity of the neurological defect. However, this association was late, occurring more than 48 hours after onset of the condition.
authors.affiliation: Unidad de Neurología, Hospital San Rafael, La Corúña, España.
authors.forename: C
authors.initials: C
authors.lastname: Vázquez-Espierrez
authors.forename: J
authors.initials: J
authors.lastname: Castillo
authors.forename: J
authors.initials: J
authors.lastname: Naveiro
authors.forename: E
authors.initials: E
authors.lastname: Martínez-Vila
mesh_terms: D000208:Acute Disease; D000368:Aged; D002545:Brain Ischemia / Q000134:cerebrospinal fluid*; D002151:Calorimetry / Q000379:methods; D005260:Female; D018698:Glutamic Acid / Q000134:cerebrospinal fluid*; D006801:Humans; D008274:Magnesium / Q000134:cerebrospinal fluid*; D008297:Male; D008875:Middle Aged
chemical_list: D018698:Glutamic Acid; D008274:Magnesium
vernacular_title: Magnesio en líquido cefalorraquídeo en la isquemia cerebral aguda: relación con la neurotoxicidad por el glutamato.