This Article Full Text Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Garciandia, A. Articles by Diez, J. Search for Related Content PubMed PubMed Citation Articles by Garciandia, A. Articles by Diez, J.

(Hypertension. 1995;25:356-364.)
© 1995 American Heart Association, Inc.

Articles

Enhanced Na⁺-H⁺ Exchanger Activity and NHE-1 mRNA Expression in Lymphocytes From Patients With Essential Hypertension

Ana Garciandia; Rafael López; Javier Tisaire; Arantxa Arrázola; Antonia Fortuño; José Bueno; Javier Diez

From the Vascular Pathophysiology Unit, Department of Internal Medicine, Center for Biomedical Research, School of Medicine, University of Navarra, Pamplona (A.G., R.L., A.A., A.F., J.D.), and the Department of Medicine, University Hospital, School of Medicine, University of Zaragoza, Zaragoza, Spain (J.T., J.B., J.D.).

Correspondence to Javier Diez, MD, PhD, Unidad de Fisiopatología Vascular, Departamento de Medicina Interna, Centro de Investigaciones Biomédicas, Facultad de Medicina, C/ Irunlarrea s/n, 31080 Pamplona, Spain.

Abstract It has been demonstrated that the activity of the sodium-proton exchanger (NHE-1 isoform) is increased in lymphocytes and other blood cells from patients with essential hypertension. In the present study, we investigated whether an increased level of NHE-1–specific mRNA in lymphocytes from patients with essential hypertension would explain the enhanced transport activity. Twenty-two hypertensive patients and 21 normotensive subjects were studied. Basal cytosolic pH was measured by the pH-sensitive fluorescent probe 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein. Maximal sodium-proton exchange activity was determined by acidifying cell pH and measuring the initial rate of the net sodium-dependent proton efflux driven by an outward proton gradient. The transcript level of NHE-1 was measured by reverse transcription–polymerase chain reaction in comparison with a constitutively expressed reference gene (ß-actin). Intracellular pH was lower in hypertensive patients than normotensive subjects (7.34±0.01 versus 7.39±0.01, mean±SEM, P<.001). The maximal activity of the sodium-proton exchanger was higher in hypertensive patients than in normotensive subjects (1262±100 versus 881±56 mmol/L cells per hour, P<.01). NHE-1 mRNA was increased in hypertensive patients compared with normotensive subjects (ratio of NHE-1 mRNA to ß-actin mRNA, 0.16±0.01 versus 0.12±0.02, P<.05). These data suggest that the increased sodium-proton exchange activity in essential hypertension may be related to the de novo synthesis of exchanger protein.

Key Words: hypertension, essential • lymphocytes • Na⁺-H⁺ exchanger • NHE-1 isoform

This article has been cited by other articles:

				J. H. Turner, M. N. Garnovskaya, S. D. Coaxum, T. M. Vlasova, M. Yakutovich, D. M. Lefler, and J. R. Raymond Ca2+-Calmodulin and Janus Kinase 2 Are Required for Activation of Sodium-Proton Exchange by the Gi-Coupled 5-Hydroxytryptamine1a Receptor J. Pharmacol. Exp. Ther., January 1, 2007; 320(1): 314 - 322. [Abstract] [Full Text] [PDF]

				S. N. Orlov, N. C. Adragna, V. A. Adarichev, and P. Hamet Genetic and biochemical determinants of abnormal monovalent ion transport in primary hypertension Am J Physiol Cell Physiol, March 1, 1999; 276(3): C511 - C536. [Abstract] [Full Text] [PDF]

				I. L. Ennis, B. V. Alvarez, M. C. C. de Hurtado, and H. E. Cingolani Enalapril Induces Regression of Cardiac Hypertrophy and Normalization of pHi Regulatory Mechanisms Hypertension, April 1, 1998; 31(4): 961 - 967. [Abstract] [Full Text] [PDF]

				W. Koren, I. Y. Postnov, and Y. V. Postnov Increased Na+-H+ Exchange in Red Blood Cells of Patients With Primary Aldosteronism Hypertension, February 1, 1997; 29(2): 587 - 591. [Abstract] [Full Text]

				O. A. Gende Chelerythrine Inhibits Na+-H+ Exchange in Platelets From Spontaneously Hypertensive Rats Hypertension, December 1, 1996; 28(6): 1013 - 1017. [Abstract] [Full Text]

				D. E. Orosz and U. Hopfer Pathophysiological Consequences of Changes in the Coupling Ratio of Na,K-ATPase for Renal Sodium Reabsorption and Its Implications for Hypertension Hypertension, February 1, 1996; 27(2): 219 - 227. [Abstract] [Full Text]

				W. Siffert and R. Dusing Sodium-Proton Exchange and Primary Hypertension : An Update Hypertension, October 1, 1995; 26(4): 649 - 655. [Abstract] [Full Text]