Location of Repository

Angiotensin-(1-7) potentiates the coronary vasodilatatory effect of bradykinin in the isolated rat heart

By A.P. Almeida, B.C. Frábregas, M.M. Madureira, R.J.S. Santos, M.J. Campagnole-Santos and R.A.S. Santos

Abstract

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

Topics: angiotensin-(1-7), bradykinin, coronary artery, rat heart, L-NAME, prostaglandins, bradykinin potentiation, Biology (General), QH301-705.5, Science, Q, DOAJ:Biology, DOAJ:Biology and Life Sciences, Medicine (General), R5-920, Medicine, R, DOAJ:Medicine (General), DOAJ:Health Sciences
Publisher: Associação Brasileira de Divulgação Científica
Year: 2000
DOI identifier: 10.1590/S0100-879X2000000600012
OAI identifier: oai:doaj.org/article:3ae8103620304cc989d504297efc5232
Journal:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • https://doaj.org/toc/1414-431X (external link)
  • https://doaj.org/toc/0100-879X (external link)
  • http://www.scielo.br/scielo.ph... (external link)
  • https://doaj.org/article/3ae81... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.