17beta-estradiol effect on the extracellular concentration of amino acids in the glutamate excitotoxicity model in the rat

Neurochem Res. 2002 Dec;27(12):1677-83. doi: 10.1023/a:1021695213099.


Estrogen has demonstrated a neuroprotective role in a rat model of glutamate excitotoxicity and other neurodegenerative disorders. We studied the effect of 17beta-estradiol on glutamate-induced increases in amino acids levels (aspartate, histidine, taurine and GABA) in the rat cortex. Local perfusion of glutamate produced a transient increase of aspartate, histidine, taurine and GABA in the extracellular fluid. Pretreatment with 17beta-estradiol significantly reduced the increases of taurine and moderately attenuated that of histidine, whereas aspartate and GABA releases were not modified. The effect of 17beta-estradiol on histidine release was reversed by the antiestrogen tamoxifen, suggesting a receptor-dependent mechanism. Good correlations between the volumes of the glutamate-induced lesions and the extracellular concentrations of taurine and aspartate were observed. These findings suggest that the attenuation of the glutamate-induced release of taurine by 17beta-estradiol may participate in the neuroprotective effects of 17beta-estradiol and that increased levels of aspartate and taurine are markers for the severity of the glutamate-induced cortical lesions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / metabolism*
  • Animals
  • Brain / drug effects
  • Brain / metabolism
  • Estradiol / pharmacology*
  • Glutamic Acid / toxicity*
  • Immunohistochemistry
  • Male
  • Microdialysis
  • Rats
  • Rats, Wistar


  • Amino Acids
  • Glutamic Acid
  • Estradiol