Conn's Syndrome is a condition where the adrenal glands over produce the mineralocorticoid hormone aldosterone. This hormone acts in conjunction with renin and angiotensin to regulate the volume of circulating blood through subtle alterations in the amount of sodium and hence water reabsorption in the kidneys. Aldosterone increases the amount of sodium reabsorbed in the kidney and by osmosis draws water along with it. This action is usually counterbalanced to homeostatically maintain normal blood volume. However, in Conn's Syndrome the cells of the adrenal cortex which secrete aldosterone multiply and secrete independently of their normal regulation. As a consequence, blood volume increases and the person becomes, usually severely, hypertensive.