Erythrocyte Na+/K(+)-ATPase and membrane and serum lipid profiles: as related to alcohol, body mass index and blood pressure.

Erythrocyte Na+/K(+)-pump activities have been measured in hypertensives, alcohol consumers and obese persons, but the results have been variously reported as decreased, increased or unchanged. We analyzed the relationships between erythrocyte Na+/K(+)-ATPase activities and the membrane and serum lipid profiles in 83 middle-aged men, to clarify the reasons for these inconsistencies. Increases in erythrocyte Na+/K(+)-ATPase activity related closely to decreases in cholesterol to phospholipid (C/P) ratio of the erythrocyte membrane. Decreases in the C/P ratio in turn related closely to elevations of serum triglycerides (TG) with increasing body mass index, and weakly to the volume of alcohol consumed. Thus, erythrocyte Na+/K(+)-ATPase activities depend largely on the membrane and serum lipid profiles as related to body weight and alcohol consumption, and which may be a cause of the previous conflicting findings. Erythrocyte Na+/K(+)-ATPase showed a positive association with blood pressure, independently of age, body mass index and serum gamma-glutamyl transpeptidase levels. Although the biological link of elevated erythrocyte Na+/K(+)-ATPase with the rise in blood pressure remains unclear, it may be a reflection of hyperinsulinemia in the subjects with a higher blood pressure due to overweight or excessive alcohol consumption.