Cardiovascular effects of small peptides of the renin angiotensin system.

The renin-angiotensin system (RAS) is a unique hormonal cascade which is composed by multiple enzymes and effector peptides. Recently, new peptides presenting biological activity have been discovered, increasing the complexity of the RAS Here, we evaluated the effects of small peptides of the RAS in coronary bed of rats. Firstly, we examined the direct effect of small angiotensinergic peptides [Angiotensin (Ang) -(1-5), Ang-(1-4) Ang-(1-3), and Ang-(1-2)] in coronary vessels.

Vasodilator Effect of Angiotensin-(1-7) on Vascular Coronary Bed of Rats: Role of Mas, ACE and ACE2.

Background: Angiotensin(Ang)-(1-7) is a biologically active member of the reninangiotensin system that participates of the regulation of blood pressure. Although Ang-(1-7) is able to potentiate the vasodilator effect of bradykinin in coronary bed of rats, a direct vasodilator effect of Ang-(1-7) in this vascular bed has not been characterized.

Objectives: The aim of this study was to evaluate the mechanisms involved in the vasodilator effect of Ang-(1-7) in the vasculature of isolated rat hearts perfused according to the Langendorff technique at constant flow.

Effects of severe caloric restriction from birth on the hearts of adult rats.

There has been increasing evidence suggesting that a severe caloric restriction (SCR) (above 40%) has beneficial effects on the hearts of rats. However, most of the reports have focused on the effects of SCR that started in adulthood. We investigated the consequences of SCR on the hearts of rats subjected to SCR since birth (CR50).

Angiotensin-converting enzyme 2 activation improves endothelial function.

Diminished release and function of endothelium-derived nitric oxide coupled with increases in reactive oxygen species production is critical in endothelial dysfunction. Recent evidences have shown that activation of the protective axis of the renin-angiotensin system composed by angiotensin-converting enzyme 2, angiotensin-(1-7), and Mas receptor promotes many beneficial vascular effects. This has led us to postulate that activation of intrinsic angiotensin-converting enzyme 2 would improve endothelial function by decreasing the reactive oxygen species production.

Cardiovascular effects of angiotensin A: a novel peptide of the renin-angiotensin system.

Introduction: Angiotensin (Ang) A was first identified in human plasma and it differs from Ang II in Ala(1) instead of Asp(1). Here, we hypothesized that the actions of this peptide might explain, at least partially, the limited effects of AT1R antagonists in certain cardiovascular diseases.

Materials And Methods: The effects of Ang A and Ang II on blood pressure (BP) and heart function were compared.

Oral administration of an angiotensin-converting enzyme 2 activator ameliorates diabetes-induced cardiac dysfunction.

We evaluated the hypothesis that activation of endogenous angiotensin-converting enzyme (ACE) 2 would improve cardiac dysfunction induced by diabetes. Ten days after diabetes induction (streptozotocin, 50 mg/kg, i.v.

The angiotensin-(1-7)/Mas receptor axis is expressed in sinoatrial node cells of rats.

The authors' previous studies have indicated that angiotensin(Ang)-(1-7) protects the heart against reperfusion arrhythmias. The aim of this study was to determine whether a functional angiotensin-converting enzyme2 (ACE2)/Ang-(1-7)/Mas receptor axis is present in the sinoatrial node (SAN) of Wistar rats. SAN cells were identified by Masson's trichrome staining, HCN4 expression, and lack of connexin43 expression.

[Wolff-Parkinson-White syndrome and the sinus venosus atrial septal defect association].

The Wolff-Parkinson-White syndrome (WPW) and sinus venosus atrial septal defect (ASD) association is very rare and not yet reported in the literature. It is the main basis for this case report.