Erythrocyte sodium - lithium countertransport in chinese: Its relationship to family history of hypertension

Rates of sodium (Na⁺) - stimulated lithium (Li ⁺) efflux (Na⁺-Li⁺ countertransport) and ouabain-sensitive Na⁺ efflux (Na⁺ pump) were determined in erythrocytes of Chinese normotensive and hypertensive subjects. Near-maximal rate of Na⁺ - Li⁺ countertransport was found to be significantly higher in hypertensive than normotensive subjects. No significant difference was observed for the rate of Na⁺ pump between them. A second series of study involved normotensive subjects without and with hypertensive parent(s) (group A and B, respectively) and hypertensive subjects (group C). We found that the rate of Na⁺ - Li⁺ countertransport in group A was significantly lower than that of group B and C, while no difference existed between group B and C. No significant difference was observed for the rate of Na⁺ pump among the three groups. Our results suggested that Na⁺-Li⁺ countertransport activity could be a genetic marker for essential hypertension in Chinese, similar to that as proposed in Caucasians.