Localization of the endothelin system in aldosterone-producing adenomas

• Autores: Egidy, Giorgia; Baviera, Erno; Ciuffo, Gladys Maria; Corvol, Pierre; Pinet, Florence
• Año de publicación: 2001
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: ENDOTHELIN; HYPERTENSION, ENDOCRINE; RECEPTORS, ENDOTHELIN; REGIONAL BLOOD FLOW; IMMUNOHISTOCHEMISTRY
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Endothelin-1 (ET-1) could play a role in the regulation of aldosterone secretion of the human adrenal gland. The presence of the endothelin-converting enzyme 1 (ECE-1) and ET-1 suggests that there is a local ET system in the adrenal cortex, but the in situ synthesis of ET-1 remains to be confirmed. The cellular distribution of the whole ET system was evaluated in 20 cases of aldosterone-producing adenomas. Polymerase chain reaction studies gave strong signals for ECE-1 mRNA and the mRNAs for endothelin type A (ETA) and B (ETB) receptors and faint signals for prepro-ET-1 mRNA. In situ hybridization showed ETA receptors scattered throughout the adenoma, in both secretory cells and vascular structures (score, +). There were more ETB receptors (score, + +), but they were restricted mainly to the endothelium. ECE-1 mRNA and protein were ubiquitous and abundant in secretory cells (score, + + +) and vascular structures (score, + +); the enzyme was active on big ET-1. There was no prepro-ET-1 mRNA in the cortex, except in the thickened precapillary arterioles present in only 30% of the aldosterone-producing adenomas studied. ET-1 immunoreactivity was detected in vascular structures (score, +), probably bound to receptors, suggesting that ET-1 has an endocrine action. The low concentrations of ET-1 could also indicate that it acts in a paracrine-autocrine fashion to control adrenal blood flow. The discrepancy between the concentrations of ECE-1 and its substrate suggests that ECE-1 has another role in the adrenal secretory cells. Our data indicate that ET probably is not a primary cause of the development or maintenance of the adenoma.
Fil: Egidy, Giorgia. Collège de France; Francia
Fil: Baviera, Erno. Collège de France; Francia
Fil: Ciuffo, Gladys Maria. Collège de France; Francia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina
Fil: Corvol, Pierre. Collège de France; Francia
Fil: Pinet, Florence. Collège de France; Francia