Internal Balance: Sodium Test

Sodium (Na+) analysis measures the concentration of this essential cation (positive ion) in blood serum. Sodium is the primary regulator of water distribution in the body and extracellular fluid volume via osmotic pressure. It is also essential for nerve impulse transmission and muscle contraction. Its level is precisely regulated by the kidneys and hormones (such as aldosterone and ADH), reflecting a delicate balance between food and water intake and excretion.