Table 1 Main physiological effects of angiotensin (Ang) II
Organ system | Physiological effects |
|---|---|
Vascular | Vasoconstriction of venous and arterial vessels Increased vascular permeability by inducing VEGF |
Renal | Stimulation of Na reabsorption and H+ excretion in the proximal tubule via the Na/H+ exchanger Stimulation of the release of aldosterone, which stimulates the distal tubule and collecting ducts of the kidneys to re-absorb sodium and water Variable effects on glomerular filtration and renal blood flow depending on the physiological and pharmacological setting: i) Constriction of the afferent and efferent glomerular arterioles; although this will tend to restrict renal blood flow, the effect on the efferent arteriole is markedly greater, and as a result, this tends to increase or maintain GFR ii) Constriction of the glomerular mesangium, thereby reducing the area for glomerular filtration iii) Enhanced sensitivity to tubuloglomerular feedback and thereby prevention of excessive rise in GFR iv) Stimulation of local release of prostaglandins, which oppose the effect of Ang II and antagonize renal vasoconstriction |
Endocrine | Stimulation of the secretion of vasopressin from the posterior pituitary gland Secretion of ACTH in the anterior pituitary gland Enhancement of release of norepinephrine by direct action on postganglionic sympathetic fibers |
Nervous | Enhancement of norepinephrine secretion |
Cardiac | Mediation of cardiac remodeling through activated tissue RAS in cardiac myocytes |
Coagulation | Prothrombotic potential through adhesion and aggregation of platelets and stimulation of PAI-1 and PAI-2 |
Immune | Promotion of cell growth and inflammation Increased expression of endothelium-derived adhesion molecules Synthesis of pro-inflammatory cytokines and chemokines Generation of reactive oxygen species |