Oxygen-Linked Hydrogen Ion Binding of Human Hemoglobin. Effects of Carbon Dioxide and 2,3 - Diphosphoglycerate. II. Studies on Whole Blood

Abstract

Acid-base titrations were performed on oxygenated and deoxygenated blood at constant PCO₂. The BE-coefficient, - (δBlood-base excess)/(δHb-bound O₂), is 0.3 mol/mol for normal blood, varying between 0 and 0.4 with variations in pH, PCO₂, and 2,3-diphosphoglycerate concentration. The ratio between the BE-coefficient for a given plasma pH and the Haldane coefficient (-δHb-bound H⁺)/(δHb-bound O₂)) for the corresponding erythrocyte pH is found to be 0.77. Comparison of the two coefficients indicates that (Ery-pH)=0.796 (Plasma-pH) + 1.356.

Key Words:

• Acid-base equilibrium
• blood
• Bohr effect
• carbamino-CO₂
• carbon dioxide
• 2,3-diphosphoglycerate
• Haldane effect
• hemoglobin
• hydrogen ion concentration
• oxygen