pH Effect on Erythropoietin Response to Hypoxia

Abstract

Six normal volunteers were exposed to a simulated altitude of 4500 meters, and changes in urine and serum erythropoietin levels were related to the changes in acid-base status. During the initial six hours of exposure the volunteers had respiratory alkalosis, which produced a definite increase in red-cell oxygen affinity. These conditions were associated with an increase in urinary and serum erythropoietin. The continued alkalosis and hypocapnia gradually raised red-cell 2,3-diphosphoglycerate concentrations and lowered red-cell oxygen affinity. These changes are thought to lead to the decreased erythropoietin concentration seen after continued exposure.