Maximum absorption of HCO3- occurs in:
Bicarbonate: 80% of bicarbonate reabsorption occurs in the PCT, 10% in thick ascending limb of LOH, and remaining in the DCT and collecting duct. Filtered bicarbonate can be reabsorbed only when it combines with H+.
PCT
DCT
collecting duct
ascending limb of the loop of Henle
Excretory System (Kidney, Bladder) Acid-Base Balance