THE KINETICS OF BICARBONATE REABSORPTION DURING ACUTE RESPIRATORY ACIDOSIS*

Abstract

Studies of renal bicarbonate reabsorption in acute respiratory acidosis have demonstrated a curvilinear rise in reabsorption as plasma bicarbonate concentration was progressively elevated from 24 to 55 meq/1. The average final value for bicarbonate reabsorption was 3.8 meq/100 ml of glomerular filtrate. Frank excretion of bicarbonate began at a plasma level of approximately 26-30 meq/L. The relationship between plasma bicarbonate concentration and the rate of bicarbonate reabsorption has been found to have the form.[image].As a tentative explanation for these findings it has been suggested that during acute respiratory acidosis an enzymatic reaction involving carbonic anhydrase is rate-limiting in the process of bicarbonate reabsorption.