Hemoglobinemia in mice exposed to high altitude

Male and female mice were exposed to a simulated altitude of 5,500m for 10, 30 or 90 days. After exposure to altitude for 90 days one group of each sex was then returned to sea level pressures for 10 days. In addition to the expected increases in hematocrit and hemoglobin, altitude exposure increased the 2,3-DPG content of red cells. Maximum values of 2,3-DPG (μmoles/g hemoglobin) occurred after 10 days at altitude and thereafter declined to values comparable to those in sea level mice despite continued exposure to hypoxia.