Effect of a dietary acid load on the plasma bicarbonate (HCO3) concentration (dashed line; in mEq/L) and urinary ammonium (NH4) excretion (solid line; in mEq/day) in normal subjects. Ammonium excretion increased almost fourfold despite a minimal fall in the plasma bicarbonate concentration.
Data from Welbourne T, Weber M, Bank N. The effect of glutamine administration on urinary ammonium excretion in normal subjects and patients with renal disease. J Clin Invest 1972; 51:1852.