On the Seemingly Diminished Co2-Bohr Effect in Hypoxic Chemodenervated Rabbits
The O2-Hb dissociation curve (ODC) in mammalian blood representing the O2-Hb saturation as function of the O2 partial pressure has multiple underlying influences. The position of the ODC as well as the magnitude of the Bohr effects show considerable species differences. This may be partly due to intrinsic properties of the different hemoglobins and partly due to different concentrations of organic phosphates (Bartels and Baumann, 1977). Furthermore, the Bohr shift is numerically greater if a pH change is caused by CO2 than if it is caused by fixed acids (Wranne et al., 1972; Bauer, 1974; Duhm, 1976). This implies that the position of the ODC can only be determined, if accompanying acid-base changes of respiratory or metabolic origin are thoroughly distinguished. The general question arises whether this requirement can be sufficiently fulfilled under in vivo conditions. During hypoxia in vivo, respiratory (high altitude, asphyxia) or metabolic (anaerobic glycolysis) acid-base disturbances of various degrees may occur at the same time, far from representing well defined boundary conditions.
KeywordsLactic Acid Respiratory Alkalosis Rabbit Blood Bohr Effect Carotid Sinus Nerve
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