Vascular and autonomic function as early predictive biomarkers of the progression to gestational hypertension.

Background: The changes in endothelial function, arterial stiffness, and heart rate variability (HRV) produced in the first trimester of pregnancy in women who develop gestational hypertension (GH) are still being investigated. Objective: to evaluate the HVR, endothelial function, and arterial stiffness changes during the first trimester of pregnancy and their relationship with the development of GH.

Methods: A group of women normotensive during the first trimester (n = 43), who later did (GH; n = 11) or did not (no-GH; n = 32) develop GH in that pregnancy, were enrolled.

A novel endothelium-independent effect of insulin on basal vascular tone in cafeteria diet-induced hypertensive rats.

Insulin vasorelaxant effect in metabolic syndrome has been shown on precontracted vessels. However, the insulin effects on basal vascular tone and its interrelationship with nitric oxide (NO) and K-channels are unknown. To test the effect of insulin on the basal vascular tone in isolated aortic rings from the cafeteria diet-induced hypertensive rats and to determine the role of NO and K-channels on this insulin effect.

Changes in vascular function and autonomic balance during the first trimester of pregnancy and its relationship with the new-born weight.

This study aimed to evaluate vascular function changes and autonomic balance during the first trimester of pregnancy and its relationship with the new-born weight. This prospective study performed in pregnant (PG) women and after delivery (not pregnant: NPG) evaluated the endothelial function (EF) and arterial stiffness (AS) by a non-invasive method. We evaluated the heart rate variability (HRV), parasympathetic nervous system (PNS), sympathetic nervous system (SNS) indexes by electrocardiogram (5 min) and the urinary nitrite excretion (NOx).

Disparate Effect of Antioxidant Supplements on the Basal Tone and Vascular Remodeling of the Aorta in Hypertensive Rats.

Background: Oxidative stress plays an essential role in the vascular tone in hypertension; however, the mechanisms remain unclear.

Aim: This study aimed to determine the antioxidant effect of tempol and vitamin C (Vit-C) on the basal tone and vascular remodeling of the aorta in nitric oxide (NO) deficiency-induced hypertensive rats.

Method: Male Sprague-Dawley rats were induced to hypertension by Nω-nitro-L-arginine methyl ester (L-NAME).

Vascular Function in Children with Low Birthweight and Its Relationship with Early Markers of Cardiovascular Risk.

Unlabelled: Low birthweight (LBW) increases the risk of developing cardiovascular diseases (CVD). Few studies have established its impact at early ages.

Aims: To study endothelial function (EF) and arterial stiffness (AS) and their relationship to early markers of CVD risk in children with LBW.

Arterial stiffness and endothelial function in obese children and adolescents and its relationship with cardiovascular risk factors.

Background: Obesity is related to an increase in the rates of cardiovascular disease.

Objective: To establish the impact of obesity on vascular function (endothelial function and arterial stiffness) in children and adolescents and its relationship to cardiovascular risk factors.

Methods: In obese (OB) children and adolescents, endothelial function and arterial stiffness were evaluated by a pulse plethysmography method (reactive hyperemia and index of digital volume waveforms, respectively).

The role of oxidative stress in alterations of hematological parameters and inflammatory markers induced by early hypercholesterolemia.

Aims: The investigation of the effects of a high cholesterol diet (HD) for a short-time period on hematological parameters and the potential role of oxidative stress and inflammation markers.

Main Methods: Rabbits were fed either a control diet or a diet containing 1% cholesterol (HD) for 5-6 weeks. The plasma lipid levels, C reactive protein (CRP), total red blood cells (RBC), total white blood cells (WBC), platelet count, packed cell volume (PCV) and leukocyte formula were determined.

Tempol blunts afferent arteriolar remodeling in chronic nitric oxide-deficient hypertension without normalizing blood pressure.

Background/aim: Renal preglomerular vessels play a central role in modulating renal function and injury, especially during conditions of renal hemodynamic stress such as hypertension. We evaluated whether improving the balance between nitric oxide (NO) and oxidative stress improves the morphological alterations of renal afferent arterioles that occur in NO deficiency-induced hypertension.

Methods: We measured indices of NO and oxidative stress and evaluated renal morphology and afferent arteriolar remodeling in rats treated with vehicle, L-NAME or L-NAME plus tempol (a superoxide dismutase mimetic) for 6 weeks.

Antioxidant treatment reverts increased arterial Basal tone and oxidative stress in nephrectomized (5/6) hypertensive rats.

Nonischemic 5/6 nephrectomized rat (NefR) is a model of chronic kidney disease. However, little is known about vascular dysfunction and its relation with hypertension in NefR. Aims.

Oxidative stress in hypertensive patients induces an increased contractility in vein grafts independent of endothelial function.

Objective. To evaluate the impact of oxidative stress on vascular reactivity to vasoconstrictors and on nitric oxide (NO) bioavailability in saphenous vein (SV) graft with endothelial dysfunction from hypertensive patients (HT). Methods.

Vascular hyporeactivity to angiotensin II and noradrenaline in a rabbit model of obesity.

This study was conducted to explore the vascular reactivity of angiotensin II and noradrenaline and their relationship with endothelial function in rabbits fed a high-fat diet (HFD). The animals were fed either an HFD or regular chow [control diet (CD)]. After 12 weeks, the rabbits fed the HFD showed higher blood pressure, body weight, and insulin levels.

17-Octadecynoic acid improves contractile response to angiotensin II by releasing vasocontrictor prostaglandins.

The present study investigated the role of CYP-enzymes in the modulation of vasoconstrictor responses to angiotensin II in rabbit aortae. In arteries with the endothelium-intact (E+) the CYP-inhibitor, 17-octadecynoic acid (17 ODYA), increased the efficacy to angiotensin II (17-ODYA-effect) as well as simultaneous incubation with miconazole (epoxygenase-inhibitor) and CAY 10434 (ω-hydroxylase-inhibitor). The removal of endothelium (E-) caused potentiation of the 17 ODYA-effect.

Nitric oxide modulates reactivity to angiotensin II in internal mammary arterial grafts in hypertensive patients without associated risk factors.

We investigated the effects of extraendothelial nitric oxide (NO) on angiotensin II (Ang II) reactivity in internal mammary artery (IMA) rings, as well as the impact of hypertension without associated risk factors in this response. Vascular reactivity, NO levels, and resting membrane potentials were determined in hypertensive (HT) and normotensive (NT) IMA rings. Only rings with endothelial dysfunction were included.

Inflammatory and prothrombotic activation with conserved endothelial function in patients with chronic, asymptomatic Chagas disease.

Unlabelled: Previously, our group showed a prothrombotic state in asymptomatic patients with chronic Chagas disease. The current paper studies the inflammatory status and endothelial function in these patients.

Methods: In 40 patients and 40 healthy volunteers, we evaluated prothrombotic state, blood parasitemia (molecular biology: polymerized chain reaction [PCR]-amplification), tissue factor pathway inhibitor antibodies (aTFPI), interleukin 6 (IL-6), and vascular cell adhesion molecule-1 (VCAM-1).

Hypercholesterolemia modifies angiotensin II desensitisation and cross talk between alpha(1)-adrenoceptor and angiotensin AT(1) receptor in rabbit aorta.

This study characterised the effect of a hypercholesterolemic diet on the interactions of hormone receptors in the rabbit aorta, both in homologous desensitisation to angiotensin II and cross talk between alpha(1)-adrenoceptors and angiotensin AT(1) receptors. Rabbits were fed either a normal chow or a diet containing 1% cholesterol for 6-7-weeks. Isometric contractions were measured in endothelium-intact or endothelium-removed aortic rings from control and hypercholesterolemic rabbits.

Reactivity of isolated toad aortic rings to angiotension II: the role of nitric oxide.

Little is known about the vascular actions of angiotensin II (Ang II) and nitric oxide (NO) in Amphibia. This study investigated (1) Ang II contractility, (2) NO concentrations, and (3) correlations between Ang II contractility, NO concentration and mean arterial pressure (MAP) in isolated Bufo arenarum toad aortic rings. Contractility was measured in isometric conditions, NO concentrations were determined by the Griess reaction, and MAP was determined by a direct method.

Endothelial dysfunction and improvement of the angiotensin II-reactivity in hypercholesterolemic rabbits: role of cyclooxygenase metabolites.

The aim of this paper was to study the effect of high cholesterol diet on endothelial function and vascular reactivity to angiotensin II and to test the role of vasoconstrictor cyclooxygenase metabolites in this experimental condition. Rabbits were fed with either normal chow or a diet containing 1% cholesterol for 6-7-week. Isometric contractions were measured in rubbed or unrubbed aortic rings.

Internal mammary artery grafts reactivity in hypertensive patients: role of stretching in extraendothelial nitric oxide.

Background: The internal mammary artery (IMA) used in bypass coronary surgery remains efficient for a longer time than other grafts, such as saphenous veins; however, its biological characteristics are incompletely defined.

Objective: To compare in IMA grafts from hypertensive (HT) and normotensive (NT) patients the presence of endothelium and their functionability, the response to passive stretching and basal tone, the reactivity to exogenous vasoconstrictors, the role of stretching in NO release, and the possible extraendothelial NO source.

Methods And Results: IMA rings contractility, presence of endothelium, and nitrite release were studied.

Increased NADPH oxidase activity mediates spontaneous aortic tone in genetically hypertensive rats.

NADPH oxidase is critically involved in increased blood pressure, vascular hypertrophy, inflammation and endothelial dysfunction in experimental and clinical hypertension. We hypothesized that NADPH oxidase might also play a role in the development of spontaneous aortic tone in spontaneously hypertensive rats (SHR). Wistar Kyoto rats (WKY) were used as normotensive controls.

Nitric oxide modulates angiotensin II-induced endothelial vasoconstrictor prostanoid release.

Unlabelled: This study investigated the modulation of angiotensin II-induced endothelial prostanoid release in rabbit aortic rings. Two cumulative dose response curves with 90-min washing interval were performed. Incubation with L-N(G)-nitroarginine methyl ester (L-NAME) 10(-4) M increased angiotensin II maximal contractile response (E(max)).

Structural changes in the renal vasculature in streptozotocin-induced diabetic rats without hypertension.

Background/aim: We evaluated in diabetic-streptozotocin rats (STZR) the structural changes of glomeruli, preglomerular vessels, glomerular tuft and renal parenchyma in order to determine the degree of renal injury and the presence of remodeling in afferent arterioles developed by diabetes without overimposed hypertension.

Methods: Renal mass index and histological score (glomerular number, density, tubular lesions and degree of arteriosclerosis) were estimated. In afferent arterioles the ratio of wall thickness/lumen was obtained by stereological methods.

Cross talk between angiotensin II and alpha 1 adrenergic receptors in rabbit aorta: role of endothelium.

Interaction between the renin-angiotensin system and the sympathetic nervous system has been proposed to be like a physiological regulation mechanism. The present work was designed to study the cross talk between angiotensin II and adrenergic receptors on the smooth muscle contractile response and the endothelium influence in this phenomenon. Homologous and endothelium independent desensitization of angiotensin II-contractile response was observed.

The novel serine protease PreR-Co promotes endothelium-independent vasorelaxation in rabbit aortic rings.

The effect of a novel enzyme (PreR-Co) that activates renal prorenin was studied on rabbit aortas with and without endothelium. It was tested 1) in the basal tone of nonstimulated or ANG II-sensitized rings or rings precontracted with norepinephrine (NE), PGF(2alpha), high KCl concentration, and 2) in rings pretreated with enalaprilat, losartan, PD-123319, N(omega)-nitro-l-arginine methyl ester, HOE-140, indomethacin, or serine protease inhibitors (PMSF, aprotinin, or soybean trypsin inhibitor); kallilkrein and bradykinin were also tested in ANG II-sensitized rings. PreR-Co produced a vasorelaxant effect in the basal tone and in the precontracted rabbit aorta.

Role of nitric oxide on the vasorelaxant effect of atrial natriuretic peptide on rabbit aorta basal tone.

The role of nitric oxide (NO) on the vasorelaxant effect of atrial natriuretic peptide (ANP) on the basal tone of rabbit aortic rings conditioned to angiotensin II (Ang II) was studied. ANP aortic relaxation and nitrite release were measured in the presence and absence of endothelium and a NO-synthase inhibitor. Ang II at 10(-8) M triggered a contractile response, conditioning the vessel to a vasorelaxant effect of ANP (10(-8) M).