Physiological Functions of the Kidney

Regulation of Blood Pressure and Electrolyte Balance

The kidney plays a critical role in maintaining homeostasis by regulating blood pressure and electrolyte balance.

Role in Blood Pressure Regulation

Through the renin-angiotensin-aldosterone system (RAAS), the kidneys control blood pressure. When blood pressure drops, the kidney releases renin, which activates a cascade leading to vasoconstriction and sodium retention, thereby increasing blood pressure.

Electrolyte Balance

The kidneys regulate levels of key electrolytes such as sodium, potassium, calcium, and phosphate by filtering excess amounts through urine and reabsorbing necessary ions.

Additional Functions

• Removal of metabolic wastes like urea and creatinine
• Regulation of fluid balance
• Production of erythropoietin for red blood cell formation