Angiotensin II mediates Tyr-dephosphorylation in rat fetal kidney membranes

Angiotensin II (Ang II) elicits a variety of physiological effects through specific Ang II receptors in numerous tissues. In addition, Ang II is a modulator of cellular growth and exerts a positive or negative effect on cell growth depending on which receptor subtype is activated. Expression of the...

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Detalles Bibliográficos
Autores: Alvarez, Sergio Eduardo, Fuentes, Lucia Beatriz, Ciuffo, Gladys Maria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2003
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/136436
Acceso en línea:http://hdl.handle.net/11336/136436
Access Level:acceso abierto
Palabra clave:ANG II RECEPTOR SUBTYPES
KIDNEY DEVELOPMENT
SIGNAL TRANSDUCTION
TYR-DEPHOSPHORYLATION
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:Angiotensin II (Ang II) elicits a variety of physiological effects through specific Ang II receptors in numerous tissues. In addition, Ang II is a modulator of cellular growth and exerts a positive or negative effect on cell growth depending on which receptor subtype is activated. Expression of the intrarenal AT2 receptors occurs at its highest levels in the fetal kidney, with a rapid decline after birth. In the present paper, we performed a study on the signaling mechanism of Ang II receptors in rat fetal (E20) kidney, a rich source of AT2 receptors, where both Ang II receptor subtypes are present. Ang II induces Tyr-dephosphorylation of proteins in rat fetal kidney membranes. The response is dose-dependent, with a reduction of 20% with respect to the control (100%), signal that is completely reversed by Ang II AT2 competitor PD123319. Orthovanadate, the inhibitor of phospho-Tyr-phosphatases (PTPase), reverts Ang II effect, suggesting the involvement of a protein tyrosine phosphatase. The peptide analog of Ang II, CGP42112, exhibits an agonist effect, which is dose-dependent. Thus, in rat fetal (E20) kidney, the Ang-induced protein Tyr-dephosphorylation of several proteins is mediated by AT2 receptors, mechanism that involves an orthovanadate senitive PTPase.