Rapid communication: PDF OnlyPlatelet sodium-proton exchange is increased in essential hypertensionSchmouder, Robert L.; Weder, Alan B. Author Information From the Division of Hypertension, Department of Internal Medicine, University of Michigan Hospitals, Ann Arbor, MI 48109, USA. Journal of Hypertension 7(4):p 325-330, April 1989. Buy Abstract Transmembrane sodium-hydrogen (Na±-H± ) exchange was measured indirectly in human platelets as the amiloride-sensitive change in volume during incubation in isosmotic sodium propionate. After first establishing the reproducibility of the assay, we measured propionate-activated volume increases in platelets from 24 male essential hypertensive patients and 20 male normotensives. For the entire group, platelet Na±-H± exchange was significantly (P < 0.006) higher in hypertensives compared with normotensives. Unlike red blood cell (RDC) cation transport markers of hypertension, platelet Na±-H± exchange was elevated in both black and white hypertensives. Na±-H± exchange was significantly positively correlated with diastolic blood pressure and did not correlate significantly with age, body weight or body mass index. In addition, platelet Na±-H± exchange did not correlate significantly with red blood cell lithium-sodium countertransport activity. Platelet Na±-H± exchange deserves further study as a marker for pathophysiological abnormalities in human hypertension. © Lippincott-Raven Publishers.