diarrhea GI: intestinal suction (loss of intestinal fistula HCO3) biliary fistula ② metabolic acidosis in early renal failure: normalS NH3 secretion↓ H+ secretion Renal tubular acidosis H secretion I kidney: depressant of c.a. (loss of acetazolamide HCO 3 intake of CI NaCl, nhCl Hyperkalemiadiarrhea; GI: intestinal suction (loss of intestinal fistula HCO- 3 ) biliary fistula ② metabolic acidosis in early renal failure: normal AG NH3 secretion H+ secretion Renal tubular acidosis: H+ secretion kidney: depressant of C.A. (loss of acetazolamide HCO- 3 ) intake of Cl￾NaCl, NH4Cl Hyperkalemia