Distribution and regulation of aromatase activity in the ram hypothalamus and amygdala

Charles Roselli, Fredrick Stormshak, John A. Resko

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Conversion of androgen to estrogen within the brain by cytochrome P450 aromatase is a component of the system controlling the display of normal male reproductive behavior and negative feedback inhibition of LH secretion in rams. In the present study, we used the highly sensitive 3H2O assay to measure aromatase activity in microdissected regions of the basal diencephalon and amygdala of intact and castrated rams. We found that aromatase activity was heterogeneously distributed. The highest activity was found in the medial amygdala, cortical amygdala, and bed nucleus of the stria terminalis. Intermediate levels of aromatase activity were found within the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, ventromedial hypothalamus, and lateral hypothalamus. The lowest activity was present in the septum, infundibulum/median eminence, and dorsal medial hypothalamus. After castration, aromatase was significantly reduced in the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, and infundibular nucleus/median eminence. In contrast, levels in castrate rams were unchanged in several other regions, most notably the bed nucleus of the stria terminalis and medial and cortical amygdala. These results provide a quantitative profile of aromatase activity in discrete regions of the ram hypothalamus and limbic system. They also demonstrate that aromatase activity is reduced in some, but not all brain regions after castration which suggests that different regulatory mechanisms control aromatase within different neuronal populations of the ram.

Original languageEnglish (US)
Pages (from-to)105-110
Number of pages6
JournalBrain Research
Volume811
Issue number1-2
DOIs
StatePublished - Nov 16 1998

Fingerprint

Aromatase
Amygdala
Hypothalamus
Preoptic Area
Anterior Hypothalamus
Septal Nuclei
Median Eminence
Castration
Lateral Hypothalamic Area
Middle Hypothalamus
Reproductive Behavior
Diencephalon
Limbic System
Arcuate Nucleus of Hypothalamus
Brain
Pituitary Gland
Cytochrome P-450 Enzyme System
Androgens
Estrogens

Keywords

  • Amygdala
  • Aromatase
  • CYP19
  • Cytochrome P450
  • Estrogen synthetase
  • Medial basal hypothalamus
  • Preoptic area

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Distribution and regulation of aromatase activity in the ram hypothalamus and amygdala. / Roselli, Charles; Stormshak, Fredrick; Resko, John A.

In: Brain Research, Vol. 811, No. 1-2, 16.11.1998, p. 105-110.

Research output: Contribution to journalArticle

Roselli, Charles ; Stormshak, Fredrick ; Resko, John A. / Distribution and regulation of aromatase activity in the ram hypothalamus and amygdala. In: Brain Research. 1998 ; Vol. 811, No. 1-2. pp. 105-110.
@article{479c45ea5e9748b5aedeaf1bc86574bb,
title = "Distribution and regulation of aromatase activity in the ram hypothalamus and amygdala",
abstract = "Conversion of androgen to estrogen within the brain by cytochrome P450 aromatase is a component of the system controlling the display of normal male reproductive behavior and negative feedback inhibition of LH secretion in rams. In the present study, we used the highly sensitive 3H2O assay to measure aromatase activity in microdissected regions of the basal diencephalon and amygdala of intact and castrated rams. We found that aromatase activity was heterogeneously distributed. The highest activity was found in the medial amygdala, cortical amygdala, and bed nucleus of the stria terminalis. Intermediate levels of aromatase activity were found within the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, ventromedial hypothalamus, and lateral hypothalamus. The lowest activity was present in the septum, infundibulum/median eminence, and dorsal medial hypothalamus. After castration, aromatase was significantly reduced in the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, and infundibular nucleus/median eminence. In contrast, levels in castrate rams were unchanged in several other regions, most notably the bed nucleus of the stria terminalis and medial and cortical amygdala. These results provide a quantitative profile of aromatase activity in discrete regions of the ram hypothalamus and limbic system. They also demonstrate that aromatase activity is reduced in some, but not all brain regions after castration which suggests that different regulatory mechanisms control aromatase within different neuronal populations of the ram.",
keywords = "Amygdala, Aromatase, CYP19, Cytochrome P450, Estrogen synthetase, Medial basal hypothalamus, Preoptic area",
author = "Charles Roselli and Fredrick Stormshak and Resko, {John A.}",
year = "1998",
month = "11",
day = "16",
doi = "10.1016/S0006-8993(98)00995-0",
language = "English (US)",
volume = "811",
pages = "105--110",
journal = "Brain Research",
issn = "0006-8993",
publisher = "Elsevier",
number = "1-2",

}

TY - JOUR

T1 - Distribution and regulation of aromatase activity in the ram hypothalamus and amygdala

AU - Roselli, Charles

AU - Stormshak, Fredrick

AU - Resko, John A.

PY - 1998/11/16

Y1 - 1998/11/16

N2 - Conversion of androgen to estrogen within the brain by cytochrome P450 aromatase is a component of the system controlling the display of normal male reproductive behavior and negative feedback inhibition of LH secretion in rams. In the present study, we used the highly sensitive 3H2O assay to measure aromatase activity in microdissected regions of the basal diencephalon and amygdala of intact and castrated rams. We found that aromatase activity was heterogeneously distributed. The highest activity was found in the medial amygdala, cortical amygdala, and bed nucleus of the stria terminalis. Intermediate levels of aromatase activity were found within the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, ventromedial hypothalamus, and lateral hypothalamus. The lowest activity was present in the septum, infundibulum/median eminence, and dorsal medial hypothalamus. After castration, aromatase was significantly reduced in the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, and infundibular nucleus/median eminence. In contrast, levels in castrate rams were unchanged in several other regions, most notably the bed nucleus of the stria terminalis and medial and cortical amygdala. These results provide a quantitative profile of aromatase activity in discrete regions of the ram hypothalamus and limbic system. They also demonstrate that aromatase activity is reduced in some, but not all brain regions after castration which suggests that different regulatory mechanisms control aromatase within different neuronal populations of the ram.

AB - Conversion of androgen to estrogen within the brain by cytochrome P450 aromatase is a component of the system controlling the display of normal male reproductive behavior and negative feedback inhibition of LH secretion in rams. In the present study, we used the highly sensitive 3H2O assay to measure aromatase activity in microdissected regions of the basal diencephalon and amygdala of intact and castrated rams. We found that aromatase activity was heterogeneously distributed. The highest activity was found in the medial amygdala, cortical amygdala, and bed nucleus of the stria terminalis. Intermediate levels of aromatase activity were found within the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, ventromedial hypothalamus, and lateral hypothalamus. The lowest activity was present in the septum, infundibulum/median eminence, and dorsal medial hypothalamus. After castration, aromatase was significantly reduced in the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, and infundibular nucleus/median eminence. In contrast, levels in castrate rams were unchanged in several other regions, most notably the bed nucleus of the stria terminalis and medial and cortical amygdala. These results provide a quantitative profile of aromatase activity in discrete regions of the ram hypothalamus and limbic system. They also demonstrate that aromatase activity is reduced in some, but not all brain regions after castration which suggests that different regulatory mechanisms control aromatase within different neuronal populations of the ram.

KW - Amygdala

KW - Aromatase

KW - CYP19

KW - Cytochrome P450

KW - Estrogen synthetase

KW - Medial basal hypothalamus

KW - Preoptic area

UR - http://www.scopus.com/inward/record.url?scp=0032539079&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032539079&partnerID=8YFLogxK

U2 - 10.1016/S0006-8993(98)00995-0

DO - 10.1016/S0006-8993(98)00995-0

M3 - Article

C2 - 9804911

AN - SCOPUS:0032539079

VL - 811

SP - 105

EP - 110

JO - Brain Research

JF - Brain Research

SN - 0006-8993

IS - 1-2

ER -