Tissue Na+K+ activated adenosine triphosphatase in retinol deficient albino rats.

The effect of retinol deficiency on Na+K+ ATPase was studied. Retinol deficient rat kidney, liver and spleen revealed a two to three-fold increase in ouabain sensitive Na+K+ ATPase activity in relation to controls. The activity in the controls could be stimulated more by concanavalin A than in the deficient group. The membrane-bound activity in the deficient group was more susceptible to freezing and thawing than the controls. Detergents could enhance the activity in both the groups to different levels. The enzyme revealed a high Km and Vmax for ATP and the cholesterol: phospholipid ratio was markedly decreased in the deficient group.