Abstract
Estrogen has demonstrated a neuroprotective role in a rat model of glutamate excitotoxicity and other neurodegenerative disorders. We studied the effect of 17β-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 17β-estradiol significantly reduced the increases of taurine and moderately attenuated that of histidine, whereas aspartate and GABA releases were not modified. The effect of 17β-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 17β-estradiol may participate in the neuroprotective effects of 17β-estradiol and that increased levels of aspartate and taurine are markers for the severity of the glutamate-induced cortical lesions.
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Ritz, MF., Schmidt, P. & Mendelowitsch, A. 17β-Estradiol Effect on the Extracellular Concentration of Amino Acids in the Glutamate Excitotoxicity Model in the Rat. Neurochem Res 27, 1677–1683 (2002). https://doi.org/10.1023/A:1021695213099
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DOI: https://doi.org/10.1023/A:1021695213099