title: Estrogen replacement increases spinophilin-immunoreactive spine number in the prefrontal cortex of female rhesus monkeys.
abstract: While studies have shown that estrogen affects hippocampal spine density and function, behavioral studies in humans and nonhuman primates have also implicated the prefrontal cortex in the effects of estrogen on cognition. However, the potential for similar estrogen-induced increases in spines and synapses in the prefrontal cortex has not been investigated in primates. Moreover, it is not known if such an estrogen effect would be manifested throughout the neocortex or primarily in the regions involved in cognition. Therefore, we investigated the effects of estrogen on dendritic spines in the prefrontal and primary visual cortices of young rhesus monkeys. Young female monkeys were ovariectomized and administered either estradiol cypionate or vehicle by intramuscular injection. Using an antibody against the spine-associated protein, spinophilin, spine numbers were estimated in layer I of area 46 and in layer I of the opercular portion of area V1 (V1o). Spine numbers in layer I of area 46 were significantly increased (55%) in the ovariectomy + estrogen group compared to the ovariectomy + vehicle group, yet spine numbers in layer I of area V1o were equivalent across the two groups. The present results suggest that estrogen's effects on synaptic organization influence select neocortical layers and regions in a primate model, and provide a morphological basis for enhanced prefrontal cortical functions following estrogen replacement.
authors.affiliation: Kastor Neurobiology of Aging Laboratories and Fishberg Research Center for Neurobiology, Mount Sinai School of Medicine, New York, NY 10029, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Tang
authors.forename: William G M
authors.initials: WG
authors.lastname: Janssen
authors.forename: Jiandong
authors.initials: J
authors.lastname: Hao
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Roberts
authors.forename: Heather
authors.initials: H
authors.lastname: McKay
authors.forename: Bill
authors.initials: B
authors.lastname: Lasley
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Allen
authors.forename: Paul
authors.initials: P
authors.lastname: Greengard
authors.forename: Peter R
authors.initials: PR
authors.lastname: Rapp
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Kordower
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Hof
authors.forename: John H
authors.initials: JH
authors.lastname: Morrison
mesh_terms: D000818:Animals; D002452:Cell Count / Q000379:methods; D003712:Dendrites / Q000737:chemistry* / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology*; D015914:Estrogen Replacement Therapy / Q000379:methods*; D005260:Female; D007150:Immunohistochemistry; D008253:Macaca mulatta; D008840:Microfilament Proteins / Q000032:analysis*; D009419:Nerve Tissue Proteins / Q000032:analysis*; D010052:Ovariectomy; D017397:Prefrontal Cortex / Q000737:chemistry / Q000166:cytology* / Q000187:drug effects*; D000099273:Neurabins
chemical_list: D004958:Estradiol; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; D000099273:Neurabins