First Apparent Dissociation Constant of Carbonic Acid, pK1', in Human Serum and Red Cells
NAVAL SUBMARINE MEDICAL RESEARCH LAB GROTON CT
Pagination or Media Count:
The first apparent dissociation constant of carbonic acid, pK1 of serum and red cells was determined on venous blood of ten healthy, adult, male, human subjects. pH and PCO2 of serum and red cells were analyzed electrometrically and a micromanometric method was used for the determination of total carbon dioxide content. Erythrocyte carbamino hemoglobin levels were estimated and used for the correction of erythrocyte pK1. The consistently larger values for red cell pK1 than the respective serum data may be attributive of the greater amount of carbamino hemoglobin concentration present in the erythrocytes. A simplified method for the calculation of a carbonate corrected, erythrocyte bicarbonate concentration using the experimentally determined red cell pH1 value has been formulated. The method involves the use of a regression equation relating serum and red cell pH, the equivalence of serum and red cell PCO2, along with experimentally determined red cell pK1.