what does the distal convoluted tubule reabsorb
1 Sodium absorption by the distal tubule is mediated by the hormone aldosterone. 2  Aldosterone increases sodium reabsorption. 3  Sodium and chloride (salt) reabsorption is also mediated by a group of kinases called WNK kinases. 4  There are 4 different WNK kinases, WNK1, WNK2, WNK3, and WNK4. It regulates pH by absorbing bicarbonate and secreting protons (H +) into the filtrate, or by absorbing protons and secreting bicarbonate into the filtrate. 2  Sodium and potassium levels are controlled by secreting K + and absorbing Na + .