Increased hypothalamic angiotensin-(1-7) levels in rats with aortic coarctation-induced hypertension.
Since angiotensin (Ang) (1-7) injected into the brain blocked Ang II pressor actions in rats made hypertensive by aortic coarctation (CH), we examined systemic and tissue angiotensin peptide levels, specifically concentrating on the hypothalamic Ang-(1-7) levels. Plasma, heart and kidney isolated from CH rats showed increased levels of Ang I, Ang II and Ang-(1-7) compared with the normotensive group, with Ang II being the predominant peptide in heart and kidney. In the hypothalamus, equimolar amounts of Ang II and Ang-(1-7) were found in the sham group, whereas only Ang-(1-7) levels increased in CH rats. We conclude that aortic coarctation activates systemic and tissue renin-angiotensin system. The increased central levels of Ang-(1-7) in the CH rats suggest a potential mitigating role of this peptide in central control of the hypertensive process.
Gironacci
Mariela M
MM
Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina. mariela@qb.ffyb.uba.ar
Brosnihan
K Bridget
KB
Ferrario
Carlos M
CM
Gorzalczany
Susana
S
Verrilli
María A Lopez
MA
Pascual
Mariano
M
Taira
Carlos
C
Peña
Clara
C
D000803:Angiotensin I / Q000378:metabolism*; D000804:Angiotensin II / Q000378:metabolism; D000809:Angiotensins / Q000378:metabolism; D000818:Animals; D001017:Aortic Coarctation / Q000150:complications* / Q000378:metabolism*; D006973:Hypertension / Q000209:etiology* / Q000378:metabolism*; D007031:Hypothalamus / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012084:Renin-Angiotensin System / Q000502:physiology
D000809:Angiotensins; D010446:Peptide Fragments; D000804:Angiotensin II; D000803:Angiotensin I; C118790:angiotensin I (1-7)