Effect of 17-beta-estradiol on dopamine, serotonine and GABA striatal levels in 6-hydroxydopamine-treated rats.
Intrastriatal injection (16microg) of the neurotoxic dopaminergic agent 6-hydroxydopamine (6-OHDA) in ovariectomized rats caused important reductions in striatal dopamine (DA) and serotonin (5-HT) levels and an increase in GABA content. Treatment of ovariectomized rats with estradiol (5 mg 17-beta-estradiol administered by a subcutaneous cannula) before 6-OHDA injection maintained the control levels of these neurotransmitters. The administration of estradiol after 6-OHDA injection did not lead to their recovery. These findings suggest that estradiol acts as a neuroprotectant--but not as a neuroreparatory agent--and that it might be able to attenuate striatal dopaminergic neuron degeneration caused by neurotoxic agents.
Peinado
Virginia
V
Department Animal Physiology, Faculty of Biological Sciences, Complutense University of Madrid, José Antonio Nováis 2, 28040 Madrid, Spain.
González
José Carlos
JC
Leret
María Luisa
ML
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D010052:Ovariectomy; D016627:Oxidopamine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D012701:Serotonin; D004958:Estradiol; D005680:gamma-Aminobutyric Acid; D016627:Oxidopamine; D004298:Dopamine