The effects of hormone replacement therapy on hypothalamic neuropeptide gene expression in a primate model of menopause

Ty W. Abel, Mary Lou Voytko, Naomi E Rance

Research output: Contribution to journalArticle

74 Citations (Scopus)

Abstract

Menopause is associated with increased neurokinin B (NKB) gene expression and decreased proopiomelanocortin (POMC) gene expression in the human hypothalamus. In the present study, young, ovariectomized cynomolgus monkeys were used in a model of menopause to examine the effects of hormone replacement therapy (HRT) on hypothalamic neuropeptide gene expression. A secondary goal was to determine whether HRT produces signs of estrogen toxicity in the primate hypothalamus by examining POMC neurons and microglial cells. In situ hybridization was performed using synthetic, radiolabeled, 48-base oligonucleotide probes. α-napthyl butyrate esterase histochemistry was used to visualize microglial cells. Both estrogen and estrogen plus progesterone treatments produced a marked suppression of the number of infundibular neurons expressing NKB gene transcripts. In contrast, HRT had no effect on the POMC system of neurons or the number of microglial cells in the infundibular nucleus. These results provide strong support for the hypothesis that the increased NKB gene expression in the hypothalamus of postmenopausal women is secondary to estrogen withdrawal. Conversely, these data suggest that the dramatic decline in the numbers of neurons expressing POMC gene transcripts in older women is caused by factors other than ovarian failure. Finally, we found no evidence that HRT, in doses designed to mimic currently prescribed regimens, produces signs of estrogen toxicity in the primate infundibular nucleus.

Original languageEnglish (US)
Pages (from-to)2111-2118
Number of pages8
JournalJournal of Clinical Endocrinology and Metabolism
Volume84
Issue number6
StatePublished - 1999

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Hormone Replacement Therapy
Menopause
Neuropeptides
Pro-Opiomelanocortin
Gene expression
Primates
Neurokinin B
Estrogens
Neurons
Hormones
Gene Expression
Hypothalamus
Arcuate Nucleus of Hypothalamus
Toxicity
Genes
Macaca fascicularis
Oligonucleotide Probes
In Situ Hybridization
Progesterone
Cell Count

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology, Diabetes and Metabolism

Cite this

The effects of hormone replacement therapy on hypothalamic neuropeptide gene expression in a primate model of menopause. / Abel, Ty W.; Voytko, Mary Lou; Rance, Naomi E.

In: Journal of Clinical Endocrinology and Metabolism, Vol. 84, No. 6, 1999, p. 2111-2118.

Research output: Contribution to journalArticle

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