title: Estrogen receptor α and G-protein coupled estrogen receptor 1 are localized to GABAergic neurons in the dorsal striatum.
abstract: Estrogens affect dopamine transmission in the striatum, increasing dopamine availability, maintaining D2 receptor density, and reducing the availability of the dopamine transporter. Some of these effects of estrogens are rapid, suggesting that they are mediated by membrane associated receptors. Recently our group demonstrated that there is extra-nuclear labeling for ERα, ERβ, and GPER1 in the striatum, but that ERα and GPER1 are not localized to dopaminergic neurons in this region. GABAergic neurons are the most common type of neuron in the striatum, and changes in GABA transmission affect dopamine transmission. Thus, to determine whether ERα or GPER1 are localized to GABAergic neurons, we double labeled the striatum with antibodies for ERα or GPER1 and GABA and examined them using electron microscopy. Ultrastructural analysis revealed that ERα and GPER1 are localized exclusively to extranuclear sites in the striatum, and ∼35% of the dendrites and axon terminals labeled for these receptors contain GABA immunoreactivity. Binding at membrane-associated ERα and GPER1 could account for rapid estrogen-induced decreases in GABA transmission in the striatum, which, in turn, could affect dopamine transmission in this region.
authors.affiliation: Centre for Studies in Behavioral Neurobiology (CSBN), Department of Psychology, Concordia University, Montreal, QC, Canada. Electronic address: anne.almey@gmail.com.
authors.forename: Anne
authors.initials: A
authors.lastname: Almey
authors.affiliation: Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA; Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY, USA. Electronic address: tmilner@med.cornell.edu.
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Milner
authors.affiliation: Centre for Studies in Behavioral Neurobiology (CSBN), Department of Psychology, Concordia University, Montreal, QC, Canada. Electronic address: wayne.brake@concordia.ca.
authors.forename: Wayne G
authors.initials: WG
authors.lastname: Brake
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000378:metabolism*; D047628:Estrogen Receptor alpha / Q000378:metabolism*; D005260:Female; D059330:GABAergic Neurons / Q000378:metabolism*; D017207:Rats, Sprague-Dawley; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*
chemical_list: D047628:Estrogen Receptor alpha; C520305:Gper1 protein, rat; D043562:Receptors, G-Protein-Coupled
keywords: Electron microscopy; GPR30; Membrane estrogen receptor alpha; γ-Aminobutyric acid