Data/hora: 10/06/2024 09:18:58

Provedor de dados: | Brazilian Journal of Medical and Biological Research
País: | Brazil
Título: | Oxidative stress may explain how hypertension is maintained by normal levels of angiotensin II
Autores: | Romero,J.C.; Reckelhoff,J.F.
Data: | 2000-06-01
Ano: | 2000
Palavras-chave: | Nitric oxide; Isoprostanes; Peroxynitrites; Essential hypertension.
Resumo: | It is well known that essential hypertension evolves in most patients with "near normal" levels of plasma renin activity. However, these levels appear to be responsible for the high levels of arterial pressure because they are normalized by the administration of angiotensin II converting inhibitors or angiotensin receptor antagonist. In experimental animals, hypertension can be induced by the continuous intravenous infusion of small doses of angiotensin II that are not sufficient to evoke an immediate pressor response. However, this condition resembles the characteristics of essential hypertension because the high levels of blood pressure exist with normal plasma levels of angiotensin II. It is suggested that small amounts of angiotensin whose plasma levels are inappropriate for the existing size of extracellular volume stimulate oxidative stress which binds nitric oxide forming peroxynitrite. The latter compound oxidizes arachidonic acid producing isoprostaglandin F2a (an isoprostane) which is characterized by a strong antinatriuretic vasoconstrictor renal effect. In this chain of reactions the vasoconstrictor effects derived from oxygen quenching of nitric oxide and increased isoprostane synthesis could explain how hypertension is maintained with normal plasma levels of renin.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2000000600006
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2000000600006
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.33 n.6 2000
Fonte: | info:eu-repo/semantics/openAccess