INVESTIGATION IN CKD & DIALYSIS What are the important functions of kidneys? 1] Excretory functions:- Excretory of nitrogenous waste products of metabolism, drugs, and toxins. 2] Regulatory functions:- Maintenance of body composition, the kidney regulates volume, osmolarity, electrolyte content, and concentration. The acidity of fluids in the body. 3] Synthetic or endocrinal function:- A] Production of erythropoietin, a 165-aminoacid protein produced by renal cortical interstitial cells stimulates the maturation of Erythrocytes in the bone marrow. B] 1, 25, dihydroxy vitamin D3 the active form of Vit D3, is formed by proximal tubule cells. This steroid hormone plays an important role in the regulation of body calcium and phosphate balance. C] Renin is the enzyme produced by the granular cells of the juxtaglomerular apparatus responsible for the production of angiotensin II which potent vasoconstrictor and growth factor contribute importantly to salt balance and blo...