Failure of estrogen to protect the substantia nigra pars compacta of female rats from lesion induced by 6-hydroxydopamine.

Laboratório de Fisiologia e Farmacologia do Sistema Nervoso Central, Departamento de Fisiologia e Farmacologia, Universidade Federal do Paraná, CP 19.031, 81.531-990 Curitiba, PR, Brazil.
Brain Research (Impact Factor: 2.83). 11/2003; 986(1-2):200-5. DOI: 10.1016/S0006-8993(03)03198-6
Source: PubMed

ABSTRACT The immunostaining for tyrosine hydroxylase (TH) in the substantia nigra pars compacta (SNpc) and in the ventral tegmental area (VTA) after intranigral infusion of 6-hydroxydopamine (6-OHDA, 6 microg/side) was analyzed in ovariectomized adult female Wistar rats. Estrogen replacement for 52 days (400-microg 17-beta-estradiol capsules) did not prevent the loss of TH-immunoreactive cells induced by 6-OHDA in the SNpc. This result indicates that the neuroprotective effect of dopaminergic mesencephalic cells is not observed with long-term estrogen replacement.

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Jan 22, 2015