Learn More
1. The aim of this study was to assess whether or not vasoactive nitric oxide (NO) stores exist within vascular tissue after lipopolysaccharide (LPS)-treatment. 2. Rat thoracic aortic rings (for contraction experiments) or whole thoracic aortae (for electron paramagnetic resonance (e.p.r.) spectroscopy) were incubated for 18 h at 37 degrees C in the absence(More)
1. We have recently demonstrated the formation of protein-bound dinitrosyl-iron complexes (DNIC) in rat aortic rings exposed to lipopolysaccharide (LPS) and shown that N-acetylcysteine (NAC) can promote vasorelaxation in these arteries, possibly via the release of nitric oxide (NO) as low molecular weight DNIC from these storage sites. The aim of the(More)
The distribution of phosphodiesterase (PDE) activities was studied in canine cardiac microsomal fractions separated by sucrose density gradient (fractions F1 to Fv1). These fractions were characterized by their 45Ca2+ uptake and release properties, [3H] ryanodine binding [used as sarcoplasmic reticulum (SR) markers] and their [3H]nitrendipine binding (as a(More)
We have recently shown that the β-adrenoceptor ligands CGP 12177, bupranolol, and SR 59230A (aryloxypropanolamines), but not BRL 37344 and CL 316243 (phenylethanolamines), exhibit significant affinity for α1-adrenoceptors and that CGP 12177 displays partial agonist properties at α-adrenoceptors in rat pulmonary artery. In this study, bupranolol and SR(More)
1. The aim of this work was to investigate the mechanism of vasorelaxation induced by red wine polyphenolic compounds (RWPC) and two defined polyphenols contained in wine, leucocyanidol and catechin. The role of the endothelium, especially endothelium-derived nitric oxide (NO), was also investigated. 2. Relaxation produced by polyphenols was studied in rat(More)
Cyclic nucleotide phosphodiesterase (PDE) activities were characterized in the cytosolic and post-nuclear membrane preparations of guinea pig cardiac ventricles. The cytosolic PDE activities were stimulated 5-fold by calmodulin (CaM) on both substrates (1 microM) and 1.2-fold by cGMP (5 microM) on cAMP hydrolysis. Conversely, in the membrane preparation,(More)
The inhibition of arterial tone produced by two nitric oxide (NO) derivatives of biological relevance, dinitrosyl-iron complexes with cysteine (DNIC-CYS) or with glutathione (DNIC-GSH), was compared. Both compounds induced vasorelaxation within the same concentration range (3-300 nM) in endothelium-denuded rat aortic rings. Consistent with a faster rate of(More)
This study was designed to elucidate the role of the adventitia in NO-mediated vascular effects of lipopolysaccharide (LPS). After incubation of rat aorta with LPS, the adventitia generated 3.5 times more nitrite plus nitrate than a corresponding segment of media. Control media covered by adventitia from LPS-treated aortic rings exhibited a 4 fold elevated(More)
1. The aim of this work was to investigate the effect of lipopolysaccharide (LPS) treatment on the relationship between the cytosolic Ca2+ ion concentration ([Ca2+]i) and contraction in rat resistance arteries, and the involvement of the L-arginine-nitric oxide (NO)-guanosine 3'-5' cyclic monophosphate (cyclic GMP) pathway in these effects. 2. [Ca2+]i and(More)
In order to study the conductances of the Sarcoplasmic Reticulum (SR) membrane, microsomal fractions from cardiac SR were isolated by differential and sucrose gradient centrifugations and fused into planar lipid bilayers (PLB) made of phospholipids. Using either KCl or K-gluconate solutions, a large conducting K+ selective channel was characterized by its(More)