Maximum potassium ions secretion is seen in

Saliva Maximum potassium secretion are: (1) Colon & rectum = 85 meq/l (2) Saliva = 25 meq/l (3) Others = 5 meq/l Now if we look at the total secretions: Colonic secretions = 200 ml/day so Potassium = 17 meq/day Salivary secretions = 2 litres/day so potassium = 50 meq/day Others = 5-6 litres/day so potassium = 25-30 meq/day But since colon excretes body fluids and saliva secretes body fluids: Max daily potassium secretion is Saliva Max daily potassium excretion is Colon. Ref: guyton and hall textbook of medical physiology 12 edition page number: 400,401,402