Please use this identifier to cite or link to this item:
Type: Artigo
Title: Resposta vascular de tetra-aminas de rutênio em anéis de aorta de ratos normotensos
Title Alternative: Vascular response of ruthenium tetraamines in aortic ring from normotensive rats
Author: Conceicao-Vertamatti, Ana Gabriela
Ferreira Ramos, Luiz Alberto
Calandreli, Ivy
Chiba, Aline Nunes
Franco, Douglas Wagner
Tfouni, Elia
Grassi-Kassisse, Dora Maria
Abstract: Ruthenium (Ru) tetraamines are being increasingly used as nitric oxide (NO) carriers. In this context, pharmacological studies have become highly relevant to better understand the mechanism of action involved. To evaluate the vascular response of the tetraamines trans-[RuII(NH3)(4)(Py)(NO)](3+), trans-[RuII(Cl)(NO)(cyclan)](PF6)(2), and trans-[RuII(NH3)(4)(4-acPy)(NO)](3+). Aortic rings were contracted with noradrenaline (10(-6) M). After voltage stabilization, a single concentration (10(-6) M) of the compounds was added to the assay medium. The responses were recorded during 120 min. Vascular integrity was assessed functionally using acetylcholine at 10(-6) M and sodium nitroprusside at 10(-6) M as well as by histological examination. Histological analysis confirmed the presence or absence of endothelial cells in those tissues. All tetraamine complexes altered the contractile response induced by norepinephrine, resulting in increased tone followed by relaxation. In rings with endothelium, the inhibition of endothelial NO caused a reduction of the contractile effect caused by pyridine NO. No significant responses were observed in rings with endothelium after treatment with cyclan NO. In contrast, in rings without endothelium, the inhibition of guanylate cyclase significantly reduced the contractile response caused by the pyridine NO and cyclan NO complexes, and both complexes caused a relaxing effect. The results indicate that the vascular effect of the evaluated complexes involved a decrease in the vascular tone induced by norepinephrine (10(-6) M) at the end of the incubation period in aortic rings with and without endothelium, indicating the slow release of NO from these complexes and suggesting that the ligands promoted chemical stability to the molecule. Moreover, we demonstrated that the association of Ru with NO is more stable when the ligands pyridine and cyclan are used in the formulation of the compound
Subject: Aorta
Óxido nítrico
Country: Brasil
Editor: Arquivos Brasileiros de Cardiologia
Rights: Aberto
Identifier DOI: 10.5935/abc.20140189
Date Issue: 2015
Appears in Collections:IB - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
000353056200007.pdf1.64 MBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.