Angiotensin II does the following: Increases sodium retention by decreasing the filtered load of sodium and enhancing proximal tubular sodium reabsorption Increases blood pressure (has pressor activity) Increases thirst Directly impairs water excretion Stimulates the adrenal cortex to secrete aldosterone, which increases sodium reabsorption via multiple renal mechanisms Angiotensin I can also be transformed to angiotensin III, which stimulates aldosterone release as much as angiotensin II but has much less pressor activity.