"Aldosterone is a yellow steroid hormone (mineralocorticoid family) produced by
the outer section (zona glomerulosa) of the adrenal cortex in theadrenal gland. It acts mainly on the distal tubules and collecting ducts of the nephron, the functional unit of the kidney, to cause the conservation of sodium, secretion of potassium, increased water retention, and increased blood pressure. The overall effect of aldosterone is to increase reabsorption of ions and water in the kidney -- increasing blood volume and, therefore, increasing blood pressure."
"Drugs that interfere with the secretion or action of aldosterone are in use as antihypertensives. One example is spironolactone, which lowers blood pressure by blocking the aldosterone receptor; its net effect is to reduce sodium and water retention, but increase retention of potassium. Aldosterone is part of the renin-angiotensin system."
"Its activity is reduced in Addison's disease and increased in Conn's syndrome."