Estrogen enhances the number of nigral dopaminergic neurons of adult male mice without affecting nigral neuroglial number and morphology

Abstract

Emerging evidence indicate the modulating effects of estrogen on dopaminergic neurons in the substantia nigra pars compacta (SNpc). One of the mechanisms underlying the effect of estrogen is through neuroglia. To determine whether estrogen affects the number of dopaminergic neurons and reactive astrocytes and microglia in the SNpc of male mice, 14-week-old C57Bl/6 male mice were injected with 17β-estradiol (E2) or vehicle for 10.5 days. On day 11 all mice were killed and the SNpc were collected and processed for lectin (GSI-B4) histochemistry, tyrosine hydroxylase (TH) immunohistochemistry or glial fibrillary acidic protein (GFAP) immunohistochemistry. Quantitative studies demonstrated that ..