Hemoglobin oxygen saturation

Finlay JC, Foster TH. Recovery of hemoglobin oxygen saturation and intrinsic fluorescence with a forward-adjoint model. Applied Optics 2005, 44, 1917-1933. 

Effects of the test substance on the respiratory system should be assessed appropriately. Respiratory rate and other measures of respiratory function (e.g., tidal volume or hemoglobin oxygen saturation) should be evaluated. Clinical observation of animals is generally not adequate to assess respiratory function, and thus these parameters should be quantified by using appropriate methodologies. 

V. Quaresima, S. Sacco, R. Totaro, and M. Ferrai, Noninva-sive Measurement of Cerebral Hemoglobin Oxygen Saturation Using Two Near-Infrared Spectroscopy Approaches, J. Biomed. Opt., 5(2), 201-205 (2000). 

Before discussing the factors that affect Hb affinity for O2, it is important to define the concept of hemoglobin oxygen saturation (SO2) ... 

Kl. Klungseyf, L-, And Stoa, K. F., Spectrophotometric determination of hemoglobin oxygen saturation. Rec. Trav. Chim. 74, 571 (1955). 

Bl. Befsum, H. E., Spectrophotometric determination of hemoglobin oxygen saturation in hemolyzed whole blood by means of various wavelength combinations. Scand. J. Clin. Lab. Invest. 9, 190 (1957). 

The importance of the BPG effect is evident in Figure 15.35. Hemoglobin stripped of BPG is virtually saturated with Og at a pO of only 20 torr, and it cannot release its oxygen within tissues, where the jbOg is typically 40 torr. BPG shifts the oxygen saturation curve of Hb to the right, making the Hb an Og... 

FIGURE 6-29 Substrate-activity curves for representative allosteric enzymes. Three examples of complex responses of allosteric enzymes to their modulators, (a) The sigmoid curve of a homotropic enzyme, in which the substrate also serves as a positive (stimulatory) modulator, or activator. Note the resemblance to the oxygen-saturation curve of hemoglobin (see Fig. 5-12). (b) The effects of a positive modulator (+) and a negative modulator (—) on an allosteric enzyme in which K0 5 is altered without a change in Zmax. The central curve shows the substrate-activity relationship without a modulator, (c) A less common type of modulation, in which Vmax is altered and /C0.sis nearly constant. 

Back to our hemoglobin example. When the partial pressure of oxygen is increased, the equilibrium shifts to the right. This is why giving a patient pure oxygen results in greater oxygen saturation in blood. 

F.B. Jensen, Nitric oxide formation from the reaction of nitrite with carp and rabit hemoglobin at intermediate oxygen saturations. FEBS J. 275, 3375-3387 (2008)... 

Be able to interpret oxygen saturation curves of various types of hemoglobins by relating such curves to their properties and describe how the release of 02 is affected. 

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