Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Original Article
  • Published:

Kinetic characteristics of the erythrocyte sodium-lithium countertransporter in black normotensive subjects compared with three other ethnic groups


Sodium-lithium countertransport activity has been proposed as a marker for hypertension and is lower in black compared to Caucasian subjects both with and without vascular disease. The question arises of what is the primary kinetic locus of the altered behaviour of the countertransporter in black subjects and whether this is also seen in normotensive subjects from other non-Caucasian ethnic groups. We studied the sodium-lithium countertransporter in four ethnic groups (black [n = 45], Caucasian [n = 45], Chinese [n = 40], and South Asian [n = 39]) of age-matched normotensive males (age range 18–35 y) with no first-degree family history of hypertension or diabetes. The clinical and laboratory characteristics of the subjects were similar in all four ethnic groups. Minor differences noted were: significantly higher mean height, weight and serum creatinine concentration (P < 0.001) and significantly lower plasma triglyceride concentration (P = 0.02) in the black compared to the other study groups. Sodium-lithium countertransport activity (mmol Li/l RBC h) was significantly lower in the black subjects (0.113 [0.013–0.265]) compared with the other groups (Caucasian, 0.247 [0.037–0.614]; Chinese, 0.210 [0.100–0.707]; South Asian, 0.211 [0.037–0.617]; P < 0.001). no differences were noted between the four study groups in respect of kNa. Mean (s.d.) Vmax values (mmol Li/l RBC h) were also reduced in the black subjects (0.152 [0.088]) compared to the other ethnic groups (Caucasian, 0.376 [0.159]; Chinese, 0.364 [0.182]; South Asian, 0.329 [0.155]; P < 0.001) and there was a strong relationship between countertransport activity and vmax (r > 0.52; P < 0.001; for each of the study groups). the differences in mean vmax noted between the Caucasian, South Asian and Chinese subjects were not significant.These results show that, when compared with three other selected ethnic groups, black subjects demonstrate an altered behaviour with respect to Vmax of the sodium-lithium countertransporter, which occurs in the absence of demonstrable vascular pathology.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Similar content being viewed by others

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

Hardman, T., Croft, P., Morrish, Z. et al. Kinetic characteristics of the erythrocyte sodium-lithium countertransporter in black normotensive subjects compared with three other ethnic groups. J Hum Hypertens 12, 29–34 (1998).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:


This article is cited by


Quick links