Aromatase distribution in the monkey temporal neocortex and hippocampus

doi:10.1016/j.brainres.2008.02.061

Brain Research

Volume 1209, 13 May 2008, Pages 115-127

https://doi.org/10.1016/j.brainres.2008.02.061 Get rights and content

Abstract

Numerous studies have shown that neuronal plasticity in the hippocampus and neocortex is regulated by estrogen and that aromatase, the key enzyme for estrogen biosynthesis, is present in cerebral cortex. Although the expression pattern of aromatase mRNA has been described in the monkey brain, its precise cellular distribution has not been determined. In addition, the degree to which neuronal aromatase is affected by gonadal estrogen has not been investigated. In this study, we examined the immunohistochemical distribution of aromatase in young ovariectomized female rhesus monkeys with or without long-term cyclic estradiol treatment. Both experimental groups showed that aromatase is localized in a large population of CA1-3 pyramidal cells, in granule cells of the dentate gyrus and in some interneurons in which it was co-expressed with the calcium-binding proteins calbindin, calretinin, and parvalbumin. Moreover, numerous pyramidal cells were immunoreactive for aromatase in the neocortex, whereas only small subpopulations of neocortical interneurons were immunoreactive for aromatase. The widespread expression of the protein in a large neuronal population suggests that local intraneuroral estrogen synthesis may contribute to estrogen-induced synaptic plasticity in monkey hippocampus and neocortex of female rhesus monkeys. In addition, the apparent absence of obvious differences in aromatase distribution between the two experimental groups suggests that these localization patterns are not dependent on plasma estradiol levels.

Section snippets

Aromatase in the hippocampus

While we did not carry out detailed quantitative analyzes of levels of immunoreactivity or number of labeled neurons, the pattern, extent, and intensity of aromatase immunostaining in the hippocampus was similar in all animals studied, regardless of treatment, suggesting that the presence or absence of circulating estradiol does not have obvious effects on aromatases expression or location. Aromatase-immunoreactive neurons were detected in different hippocampal regions, including the dentate

Aromatase immunoreactivity in the hippocampus

The aromatase expression patterns in the hippocampus and temporal neocortex of the female rhesus monkey, extends data from previous studies in several brain structures of different vertebrates (Sanghera et al., 1991, Shen et al., 1994, Yamada-Mouri et al., 1995, Saldanha and Schlinger, 1997, Sasano et al., 1998, Garcia-Segura et al., 1999, Stoffel-Wagner et al., 1999, Ivanova and Beyer, 2000, Saldanha et al., 2000, Wehrenberg et al., 2001, Hojo et al., 2004, Rune and Frotscher, 2005, Yague et

Experimental groups and treatment

The study was carried out in young OVX female rhesus monkey (Macaca mulatta) that received estradiol or vehicle (see Table 1). All experiments were conducted in compliance with the National Institutes of Health Guidelines for the Care and Use of Experimental Animals approved by the Institutional Animal Care and Use Committee at the University of California-Davis.

Eight young female rhesus monkeys (mean age ± SEM, 10 years ± 3 months) were used in this study. The monkeys were bilaterally OVX and were

Acknowledgments

We thank Anne Canfield, Mary Roberts, Deborah Kent, Sona Santos, and Heather McKay for technical assistance, and Dr. Don Canfield for veterinary care. Additionally, we thank Dr. Peter Rapp and Dr. Jiandong Hao for helpful discussion. This work was supported in part by NIA Grant AG016765.

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^☆: Grant sponsors: National Institutes of Health; Grant number: AG16765 (JHM). Ministerio de Educación y Ciencia, Spain; Grant number: SAF 2005-00272. European Union; Grant number: LSHM-CT-2005-518245.

¹: Due to their equal collaboration on this manuscript Josue G. Yague and Athena Ching-Jung Wang are to be noted with co-authorship.

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Research ReportAromatase distribution in the monkey temporal neocortex and hippocampus☆

Abstract

Section snippets

Aromatase in the hippocampus

Aromatase immunoreactivity in the hippocampus

Experimental groups and treatment

Acknowledgments

Brain Res.

Brain Res. Bull.

J. Steroid Biochem. Mol. Biol.

J. Chem. Neuroanat.

Prog. Neurobiol.

Brain Res.

Neuroscience

Prog. Neurobiol.

Prog. Neurobiol.

Mol. Brain Res.

Biochem. Biophys. Res. Commun.

Neurobiol. Aging

J. Steroid Biochem. Mol. Biol.

Neuroscience

Biochem. Biophys. Res. Commun.

Neuroscience

Neuroscience

Neuroscience

Neuroscience

Am. J. Obstet. Gynecol.

Gen. Comp. Endocrinol.

Brain Res.

Mol. Brain Res.

J. Steroid Biochem. Mol. Biol.

Exp. Gerontol.

Horm. Behav.

Neuroscience

Biochem. Biophys. Res. Commun.

J. Steroid. Biochem. Mol. Biol.

Exp. Neurol.

Different modes of hippocampal plasticity in response to estrogen in young and aged female rats

Proc. Natl. Acad. Sci. U. S. A.

Effect of estrogen-serotonin interactions on mood and cognition

Behav. Cogn. Neurosci. Rev.

Calcium-binding proteins selective markers of nerve cells

Cell Tissue Res.

Gonadal steroid induction of structural sex differences in the central nervous system

Annu. Rev. Neurosci.

Estradiol prevents kainic acid-induced neuronal loss in the rat dentate gyrus

NeuroReport

Gonadal hormones affect neuronal vulnerability to excitotoxin-induced degeneration

J. Neurocytol.

Brain aromatase is neuroprotective

J. Neurobiol.

Aromatase expression by reactive astroglia is neuroprotective

Ann. N.Y. Acad. Sci.

Estradiol increases pre- and postsynaptic proteins in the CA1 region of the hippocampus in female rhesus macaques (Macaca mulatta)

Endocrinology

Neocortical neuronal diversity chemical heterogeneity revealed by colocalization studies of classic neurotransmitters, neuropeptides, calcium-binding proteins and cell surface molecules

Cereb. Cortex

Gonadal hormones induce dendritic growth in the adult avian brain

Science

Distributed hierarchical processing in the primate cerebral cortex

Cereb. Cortex

Estrogen formation by the isolated perfused rhesus monkey brain

Science

17b-estradiol enhances NMDA receptor-mediated EPSPs and long-term potentiation

J. Neurophysiol.

Research Report
Aromatase distribution in the monkey temporal neocortex and hippocampus☆