The synaptic organization of VMH neurons that mediate the effects of estrogen on sexual behavior

Citation
Lm. Flanagan-cato et al., The synaptic organization of VMH neurons that mediate the effects of estrogen on sexual behavior, HORMONE BEH, 40(2), 2001, pp. 178-182
Citations number
25
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
HORMONES AND BEHAVIOR
ISSN journal
0018-506X → ACNP
Volume
40
Issue
2
Year of publication
2001
Pages
178 - 182
Database
ISI
SICI code
0018-506X(200109)40:2<178:TSOOVN>2.0.ZU;2-X
Abstract
Estrogen acts in the hypothalamic ventromedial nucleus (VMH) of female rats to promote sexual behavior, as typified by the lordosis response. Morpholo gical changes in the VMH, such as increased synaptic profiles and increased dendritic spines, suggest that estrogen may modulate behavior by altering VMH synaptic organization. To understand the significance of these changes, this laboratory has been investigating the functional classes of lordosis- relevant neurons and their local connectivity. A neurotropic virus, pseudor abies virus (PRV), was used to transneuronally label the CNS network that c ontrols the lordosis-producing muscles. When PRV was placed in the lumbar e paxial muscles, it was sequentially detected in the lumbar ventral horn, th e medullary reticular formation, the periaqueductal gray, and finally the V MH. Subsequent analysis showed that the population of VMH neurons that were initially infected with PRV largely resided beyond the cluster of estrogen receptor-containing neurons. In a separate study, VMH neurons were visuali zed with Lucifer yellow, and their morphology was analyzed using confocal m icroscopy. Such analysis confirmed that estrogen treatment increased dendri tic spines in the VMH. The particular VMH neurons in this study did not exp ress nuclear estrogen receptor, which suggests that estrogen can increase s pine density indirectly. These results represent initial steps toward unrav eling the local circuit that mediates estrogenic action on a specific repro ductive behavior. (C) 2001 Academic Press.