Estrogen Reduces Aldosterone, Upregulates Adrenal Angiotensin II AT2 Receptors and Normalizes Adrenomedullary Fra-2 in Ovariectomized Rats
Autor: | Gustavo Baiardi, Ines Armando, Ignacio M. Larrayoz-Roldan, Miroslava Macova, Jin Zhou, Dmitri Tyurmin, Juan M. Saavedra |
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Rok vydání: | 2008 |
Předmět: |
endocrine system
medicine.medical_specialty Aldosterone Angiotensin II receptor type 1 Endocrine and Autonomic Systems medicine.drug_class Adrenal cortex Endocrinology Diabetes and Metabolism Receptor expression Biology Cellular and Molecular Neuroscience chemistry.chemical_compound Endocrinology medicine.anatomical_structure chemistry Estrogen Zona glomerulosa Mineralocorticoid Internal medicine cardiovascular system medicine Adrenal medulla hormones hormone substitutes and hormone antagonists circulatory and respiratory physiology |
Zdroj: | Neuroendocrinology. 88:276-286 |
ISSN: | 1423-0194 0028-3835 |
DOI: | 10.1159/000150977 |
Popis: | We studied the effect of ovariectomy and estrogen replacement on expression of adrenal angiotensin II AT1 and AT2 receptors, aldosterone content, catecholamine synthesis, and the transcription factor Fos-related antigen 2 (Fra-2). Ovariectomy increased AT1 receptor expression in the adrenal zona glomerulosa and medulla, and decreased adrenomedullary catecholamine content and Fra-2 expression when compared to intact female rats. In the zona glomerulosa, estrogen replacement normalized AT1 receptor expression, decreased AT1B receptor mRNA, and increased AT2 receptor expression and mRNA. Estrogen treatment decreased adrenal aldosterone content. In the adrenal medulla, the effects of estrogen replacement were: normalized AT1 receptor expression, increased AT2 receptor expression, AT2 receptor mRNA, and tyrosine hydroxylase mRNA, and normalized Fra-2 expression and catecholamine content. We demonstrate that the constitutive adrenal expression of AT1 receptors, catecholamine synthesis and Fra-2 expression are partially under the control of reproductive hormones. Our results suggest that estrogen treatment decreases aldosterone production through AT1 receptor downregulation and AT2 receptor upregulation. AT2 receptor upregulation and modulation of Fra-2 expression may participate in the estrogen-dependent normalization of adrenomedullary catecholamine synthesis in ovariectomized rats. The AT2 receptor upregulation and the decrease in AT1 receptor function and in the production of the fluid-retentive, pro-inflammatory hormone aldosterone partially explain the protective effects of estrogen therapy. |
Databáze: | OpenAIRE |
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