[Renin and aldosterone]

The radioimmunological dosages of renin and of aldosterone are used nowadays in clinical practice for research purposes only. The measurement of activity of plasma renin may be considered a significant indication of the concentration of the enzime in plasma and, indirectly, of its secretion. Several factors take a part in the regulation of renin secretion (mean arterial pressure, introduction of sodium and potassium, the sympathetic nervous system, ADH and concentration of angiotensin II in plasma). In pathological conditions such factors may cause alteration of the renin-angiotensin II system, thus determining hyperreninisms and hyporeninisms, whether associated with arterial hypertension or not. Several factors take a part on aldosterone secretion too (ACTH, sodiaemia, potassiaemia, renin-angiotensin II system). In pathological conditions the alteration of the regulation system may lead to hyperaldosteronism or to hypoaldosteronism of primary or secondary type. A survey of recent research on the physiopathology of the renin-aldosterone system is also given.