Protons removal from blood

In 1931 Otto Warburg discovered that the oxidation of glucose 6-phosphate in red blood cells required both an enzyme and a heat stable coenzyme, and he later referred to the latter as the Wasserstolfubertragendes Co-Ferment , i> to distinguish it from cozymase, the coenzyme of yeast fermentation, which had been discovered many years earlier by Sir Arthur Harden. He found that the functional group in both coenzymes was nicotinamide, which acted as acceptor for the protons removed from the substrate. In addition to nicotinamide, each coenzyme also contained one adenine and two ribosyl residues, but they differed in their phosphorus content. These observations led him to name the cozymase diphosphopyridine nucleotide (DPN), and the hydrogen-transferring coenzyme tri-phosphopyridine nucleotide (TPN). ... 

Figure 6.8 Fate of lactate and protons produced by muscle and other tissues. The heart and Liver play major roles in removing both Lactate and protons from blood.

The lactate and proton concentrations, and hence the pH in the blood, depend not only on the rate of release from muscle, and other tissues, but also on the rate of their removal from the blood. The transporter that transports lactate and protons out of cells also transports them into cells. There are two tissues that are important in then-removal from the blood liver and heart (Figure 6.8). 

The Bohr effect is closely related to the major roles that hemoglobin plays in disposing of the C02 produced in tissues, and in controlling the blood pH. While oxygen is being delivered to the tissues in the venous blood, the C02 is being removed from the tissues (fig. 5.5). The C02 that diffuses into the erythrocytes is rapidly converted into carbonic acid, which in turn dissociates into H+ and HC03. The protons produced by this dissociation would lower the pH and reverse the dissociation if it were not for the buffer-... 

Production and removal of protons into and from the blood... 

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