Naunyn Schmiedebergs Arch Pharmacol
September 2024
Estrone (E1) constitutes the primary component in oral conjugated equine estrogens (CEEs) and serves as the principal estrogen precursor in the female circulation in the post-menopause. E1 induces endothelium-dependent vasodilation and activate PI3K/NO/cGMP signaling. To assess whether E1 mitigates vascular dysfunction associated with postmenopause and explore the underlying mechanisms, we examined the vascular effects of E1 in ovariectomized (OVX) rats, a postmenopausal experimental model.
View Article and Find Full Text PDFConjugated equine estrogens (CEE) have been widely used by women who seek to relieve symptoms of menopause. Despite evidence describing protective effects against risk factors for cardiovascular diseases by naturally occurring estrogens, little is known about the vascular effects of equilin, one of the main components of CEE and not physiologically present in women. In this regard, the present study aims to compare the vascular effects of equilin in an experimental model of hypertension with those induced by 17β-estradiol.
View Article and Find Full Text PDFVascul Pharmacol
November 2018
Estrone (E1) produces remarkable vascular effects, including relaxation, modulation of proliferation, apoptosis and cell adhesion. This study investigated the role of estrogen receptors and endothelial signaling pathways in the vascular relaxation promoted by E1. Aortic rings from male Wistar rats (250-300 g) were contracted with phenylephrine and stimulated with graded concentrations of E1.
View Article and Find Full Text PDFThe perivascular adipose tissue (PVAT) releases a variety of factors that affect vascular function. PVAT in the thoracic aorta shares characteristics with the brown adipose tissue, including a large amount of mitochondria. PVAT-derived factors influence both endothelial and smooth muscle function via several signaling mechanisms including the release/generation of reactive nitrogen and oxygen species.
View Article and Find Full Text PDFThe mechanisms of action involved in the vasorelaxant effect of gallic acid (GA) were examined in the isolated rat thoracic aorta. GA exerted a relaxant effect in the highest concentrations (0.4-10mM) in both endothelium-intact and endothelium-denuded aortic rings.
View Article and Find Full Text PDFHypernatremia stimulates the secretion of oxytocin (OT), but the physiological role of OT remains unclear. The present study sought to determine the involvement of OT and renal nerves in the renal responses to an intravenous infusion of hypertonic saline. Male Wistar rats (280-350 g) were anesthetized with sodium thiopental (40 mg.
View Article and Find Full Text PDFIt has been clearly established that mitogen-activated protein kinases (MAPKS) are important mediators of angiotensin II (Ang II) signaling via AT1 receptors in the vasculature. However, evidence for a role of these kinases in changes of Ang II-induced vasoconstriction in obesity is still lacking. Here we sought to determine whether vascular MAPKs are differentially activated by Ang II in obese animals.
View Article and Find Full Text PDFThe adipokine chemerin has been implicated in cardiovascular complications associated with obesity and the metabolic syndrome. Chemerin has direct effects on the vasculature, augmenting vascular responses to contractile stimuli. As NO/cGMP signalling plays a role in vascular dysfunction associated with obesity and the metabolic syndrome, we hypothesized that chemerin induces vascular dysfunction by decreasing NO/cGMP signalling.
View Article and Find Full Text PDFImpaired vascular function, manifested by an altered ability of the endothelium to release endothelium-derived relaxing factors and endothelium-derived contracting factors, is consistently reported in obesity. Considering that the endothelium plays a major role in the relaxant response to the cannabinoid agonist anandamide, the present study tested the hypothesis that vascular relaxation to anandamide is decreased in obese rats. Mechanisms contributing to decreased anandamide-induced vasodilation were determined.
View Article and Find Full Text PDFObjective: The increased risk of cardiovascular diseases in postmenopausal women has been linked to the decrease in plasma estrogen levels. Preparation of conjugate equine estrogens (CEE) is one of the most routinely used hormone therapy in postmenopausal women. However, studies on the vascular effects of CEE are still sparse and the mechanism of action is not completely elucidated.
View Article and Find Full Text PDFEvid Based Complement Alternat Med
August 2012
Caryocar brasiliense Camb. "pequi" is a native plant from the Cerrado region of Brazil that contains bioactive components reported to be antioxidant agents. Previous work has demonstrated that dietary supplementation with pequi decreased the arterial pressure of volunteer athletes.
View Article and Find Full Text PDFSex differences in Ca2+-dependent signalling and homoeostasis in the vasculature of hypertensive rats are well characterized. However, sex-related differences in SOCE (store-operated Ca2+ entry) have been minimally investigated. We hypothesized that vascular protection in females, compared with males, reflects decreased Ca2+ mobilization due to diminished activation of Orai1/STIM1 (stromal interaction molecule 1).
View Article and Find Full Text PDFClinics (Sao Paulo)
December 2010
Purpose: Bacterial translocation has been shown to occur in critically ill patients after extensive trauma, shock, sepsis, or thermal injury. The present study investigates mesenteric microcirculatory dysfunctions, the bacterial translocation phenomenon, and hemodynamic/metabolic disturbances in a rat model of intestinal obstruction and ischemia.
Methods: Anesthetized (pentobarbital 50 mg/kg, i.