| Popis: |
Publisher Summary This chapter discusses decreased Na, K–ATPase activity in erythrocyte membranes and intact erythrocytes from obese man. Obesity in rodents is associated with increased metabolic efficiency based at least in part on reduced sodium pump activity. Several recent studies in man also suggest altered metabolic rates associated with human obesity. Experimental studies were undertaken to evaluate the relationship between Na, K–ATPase and obesity in the Pima Indians, a demographically well-characterized and relatively homogeneous population with an extraordinarily high prevalence of obesity. The results demonstrate an inverse relationship between sodium pump activity and the magnitude of obesity in intact red cells as well as in isolated erythrocyte membranes. The role of this decreased erythrocyte Na, K–ATPase in the pathogenesis of human obesity is still obscure. A plausible but unproved hypothesis suggests that increased metabolic efficiency that results from a reduced expenditure of energy by the sodium pump could result in an accumulation of unused calories in the form of fat. |
