[Is aldosterone a modulator of vascular tone?]

The vascular endothelium is a dynamic tissue that is sensitive to physical and chemical stimuli. The fact that endothelial cells are directly exposed to the blood fluid components provides the ability to regulate diverse physiological functions, among them are: the coagulation, the metabolism of the vascular wall, transcapillary permeability of solutes and water, and the vascular tissue remodeling. In addition to these functions, the vascular endothelium plays a major role in local regulation and maintenance of vascular tone. This function is performed by the release of vasoactive factors such as, nitric oxide, endothelin-1, angiotensin-II, adenosine, prostacyclins, thromboxanes, free radicals, among other compounds not less important. Recent studies have suggested a new player in the control of vascular tone: the aldosterone. Thus, the recent evidence suggests that this mineralocorticoid hormone may cause vasoconstriction in pathophysiological conditions, through modulating the gene expression and activity of endothelin-1, glucose 6 phosphate deshydrogenase and Rho kinase, as well as by altering the phosphorylation and activity of endothelial nitric oxide synthase (eNOS). It has also been observed involvement of aldosterone in the generation of oxidative stress, action exerted indirectly through reduction of the bioavailability of nicotinamide adenine dinucleotide phosphate (NADPH). Therefore, this review focuses on describing some of the mechanisms involved in the regulation of vascular tone and review studies that show recent evidence of the role of aldosterone as a mediator of this function.