What is the role of renin in the secretion of aldosterone?

Aldosterone is a hormone which is produced by the adrenal glands which are present above the kidneys. The role of aldosterone is to regulate the blood pressure. It causes the reabsorption of water and salts into the bloodstream during the kidney filteration process. Hence, maintains the blood volume, restors blood pressure and salt level.

Renin is an enzyme. It facilitates chemical reactions which stimulates the synthesis of angiotension II, it directs the synthesis of aldosterone.