Aldosterone increases RAMP1 expression in mesenteric arteries from spontaneously hypertensive rats.
OBJECTIVE
We analysed the effect of aldosterone on calcitonin gene-related peptide (CGRP) mediated vasodilation in noradrenaline precontracted endothelium denuded mesenteric arteries segments from Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) and the effect of aldosterone on calcitonin receptor-like receptor (CL receptor) and receptor activity modifying protein 1 (RAMP1) expression in endothelium-denuded mesenteric arteries from SHR rats.


RESULTS
CGRP 0.1 nM-0.1 microM induced a concentration-dependent relaxation that was enhanced by aldosterone 1 microM in SHR only. Incubation with RU 486 10 microM significantly reduced the enhancement of CGRP-relaxation produced by aldosterone in SHR. CL receptor expression was not modified in either strain, while RAMP1 expression was enhanced in SHR by aldosterone 1 microM 120 min and 0.1 microM 120 min. This up-regulation of RAMP1 was prevented by RU 486 10 microM.


CONCLUSIONS
Aldosterone, through glucocorticoid receptor activation, increases the vasodilatory effect of CGRP in SHR mesenteric arteries, which seems to be mediated by increased RAMP1 expression.
Márquez-Rodas
Iván
I
Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain.
Longo
Federico
F
Aras-López
Rosa
R
Blanco-Rivero
Javier
J
Diéguez
Elena
E
Tejerina
Teresa
T
Ferrer
Mercedes
M
Balfagón
Gloria
G
D000450:Aldosterone / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D015153:Blotting, Western; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism / Q000494:pharmacology; D058286:Calcitonin Receptor-Like Protein; D004305:Dose-Response Relationship, Drug; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008638:Mesenteric Arteries / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011918:Rats, Inbred SHR / Q000378:metabolism*; D011921:Rats, Inbred WKY; D058261:Receptor Activity-Modifying Proteins; D018003:Receptors, Calcitonin / Q000378:metabolism; D014664:Vasodilation / Q000187:drug effects
D058286:Calcitonin Receptor-Like Protein; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D058261:Receptor Activity-Modifying Proteins; D018003:Receptors, Calcitonin; D000450:Aldosterone; D015740:Calcitonin Gene-Related Peptide