Intracellular cation concentrations in essential hypertension and chronic renal failure

in Clinical & Experimental Hypertension (1993), 15(3), 461-478

The aim of this study was to test basal and after treatment erythrocyte sodium and calcium concentrations, and calcium-ATPase activity and platelet cytosolic free calcium and pH in 20 normotensive ... [more ▼]

The aim of this study was to test basal and after treatment erythrocyte sodium and calcium concentrations, and calcium-ATPase activity and platelet cytosolic free calcium and pH in 20 normotensive controls, 20 hemodialysis-dependent chronic renal failure patients and in 18 essential hypertensives. Prior to treatment, essential hypertensive and uremic patients presented similar higher platelet calcium concentrations and lower pH than the normotensive control group. The erythrocyte sodium, calcium, and magnesium concentrations were only significantly elevated in chronic renal failure, with a significant decrease in the calcium-ATPase activity in the latter population. Hemodialysis partially reversed these intracellular ionic abnormalities with normalization of platelet pH. Significant correlations have been noted between weight loss and decreases in platelet calcium concentration (r = 0.60, p < 0.01) or in erythrocyte sodium (r = 0.50, p < 0.05). The systolic blood pressure decrease was only correlated to the increase in calcium-ATPase activity (r = 0.57, p < 0.05). Antihypertensive treatment (captopril and nifedipine) only tended to normalize the intracellular calcium concentration with correlation between the decrease of the latter and blood pressure decrease (r = 0.64 for the systolic blood pressure and 0.68 for the diastolic blood pressure, p < 0.01). Thus, in essential hypertension and in uremia, some cellular ionic abnormalities exist in platelets in baseline condition. Moreover, in uremia, erythrocyte presents abnormal ionic pattern. Some, but not all of these abnormalities could be corrected by treatment affecting blood pressure (cellular calcium) in essential hypertension or by hemodialysis (cellular sodium, calcium, and pH). In the latter treatment, the changes are linked to extracellular fluid modification. In essential hypertension, the intracellular calcium reduction was linked to blood pressure decrease. [less ▲]

Red Blood Cell Na-Li Countertransport, Hypertensive Heredity, and Cardiovascular Risk in Young Adults

in American Journal of Hypertension : Journal of the American Society of Hypertension (1993), 6(4), 314-316

The erythrocyte Na-Li countertransport (CT) has been considered as a marker of genetic propension to essential hypertension, but also to be linked to atherosclerosis risk factors. We have evaluated these ... [more ▼]

The erythrocyte Na-Li countertransport (CT) has been considered as a marker of genetic propension to essential hypertension, but also to be linked to atherosclerosis risk factors. We have evaluated these relationships by measuring the Na-Li CT, blood pressure levels, the family predisposition to hypertension, body mass index, subscapular skin-fold thickness, waist/hip ratio, and plasma lipids in 43 young adults (22 to 23 years; 13 with a positive family history of hypertension), followed since adolescence (+/- 10 years) to analyze the natural history of blood pressure in this period of life. The Na-Li CT was negatively correlated with the HDL cholesterol (r = -0.37) and the HDL cholesterol/total cholesterol ratio (r = -0.44). This transport system was positively correlated to family history of hypertension (r = 0.38), waist/hip ratio, and the diastolic blood pressure. When the family history of hypertension was present, Na-Li CT and diastolic blood pressure were higher (P < .05), but the HDL cholesterol was lower (P < .01). After separating people according to the blood pressure level during adolescence in two groups, one lower than the 75th percentile (P75), and one higher, we notice that the latter remains characterized by a higher systolic blood pressure. But neither the Na-Li CT nor family history of hypertension and plasma lipids could explain the difference in the blood pressure behavior during this period. Thus, an increase of RBC Na-Li CT activity in young adults would suggest a higher cardiovascular risk rather than to be a simple marker of a hypertensive risk. [less ▲]

Does salt restriction lower the intracellular calcium concentration in essential hypertension?

in Journal of Hypertension (Supplement) (1992), 10

Plasma Na-K ATPase inhibitor activity and intracellular ions in volume expanded hypertension

in European Journal of Clinical Investigation (1991), 21