<qa>  What is the effect of aldosterone and sodium to rats?1. Endothelial dysfunction: The administration of aldosterone and sodium to rats results in transmural coronary arterial inflammation with monocyte and macrophage infiltration and the expression of inflammatory markers such as COX-2, MCP-1 and VCAM-1. The administration of an aldosterone antagonist markedly reduced this inflammatory response. Although a similar response occurred with infusion of ANG II, this was in part dependent on aldosterone synthesis as it was reduced by adrenalectomy but restored by aldosterone infusion. In vitro, vascular endothelial fibrinolysis is inhibited by aldosterone as a result of an increase in plasminogen activator inhibitor PAI-1. In humans, primary hyperaldosteronism is associated with endothelial dysfunction compared to normal and hypertensive controls. In patients with chronic heart failure, aldosterone receptor blockade with spironolactone results in significant improvement in endothelial dependent vasodilatation and vascular nitric oxide bioactivity. 