Comparative studies of the effect of moderate and high altitude stress on human subjects: studies on erythrocyte ghost ATPases

Studies have been carried out on erythrocyte membrane‐bound ATPases of ten female subjects at a moderate altitude (2200 m) and at a high altitude (5100 m). Mg²⁺‐ATPase activity of the subjects was found to be significantly stimulated under conditions at a high altitude in comparison to that at a moderate altitude. The changes in total lipids and cholesterol contents of erythrocyte ghosts and plasma Na⁺/K⁺ levels at high altitude in comparison to the moderate altitude indicates an alteration in the membrane permeability under high altitude stress. On acclimatization of the subjects from a high to a moderate altitude, the studied parameters reverted to the values as observed at a moderate altitude.