Aldosterone. Molecular model of the steroid hormone aldosterone (C21.H28.O5). Aldosterone is released by the adrenal glands and helps maintain the body's water and electrolyte balance. It does this by increasing or decreasing uptake of sodium and potassium into tissues. Excess aldosterone levels in the blood can lead to high blood pressure and muscle weakness. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white) and oxygen (red).