Data/hora: 07/06/2024 02:48:22

Provedor de dados: | 56
País: | Brazil
Título: | Angiotensin-(1-7) potentiates the coronary vasodilatatory effect of bradykinin in the isolated rat heart
Autores: | Almeida,A.P.; Frábregas,B.C.; Madureira,M.M.; Santos,R.J.S.; Campagnole-Santos,M.J.; Santos,R.A.S.
Data: | 2000-06-01
Ano: | 2000
Palavras-chave: | Angiotensin-(1-7); Bradykinin; Coronary artery; Rat heart; L-NAME; Prostaglandins; Bradykinin potentiation.
Resumo: | It has been shown that angiotensin-(1-7) (Ang-(1-7)) infusion potentiates the bradykinin (BK)-induced hypotensive response in conscious rats. The present study was conducted to identify Ang-(1-7)-BK interactions in the isolated rat heart perfused according to the Langendorff technique. Hearts were excised and perfused through the aortic stump under a constant flow with Krebs-Ringer solution and the changes in perfusion pressure and heart contractile force were recorded. Bolus injections of BK (2.5, 5, 10 and 20 ng) produced a dose-dependent hypotensive effect. Ang-(1-7) added to the perfusion solution (2 ng/ml) did not change the perfusion pressure or the contractile force but doubled the hypotensive effect of the lower doses of BK. The BK-potentiating Ang-(1-7) activity was blocked by pretreatment with indomethacin (5 mg/kg, ip) or L-NAME (30 mg/kg, ip). The Ang-(1-7) antagonist A-779 (50 ng/ml in Krebs-Ringer) completely blocked the effect of Ang-(1-7) on BK-induced vasodilation. These data suggest that the potentiation of the BK-induced vasodilation by Ang-(1-7) can be attributed to the release of nitric oxide and vasodilator prostaglandins through an Ang-(1-7) receptor-mediated mechanism.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2000000600012
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2000000600012
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.33 n.6 2000
Fonte: | info:eu-repo/semantics/openAccess