A RELATIONSHIP BETWEEN DISORDERS OF ERYTHROCYTE-MEMBRANE PERMEABILITY FOR UNIVALENT IONS AND INTRACELLULAR CALCIUM DISTRIBUTION IN PRIMARY ARTERIAL-HYPERTENSION

  • 1 January 1984
    • journal article
    • research article
    • Vol. 24  (3) , 87-95
Abstract
The relation of electric potential, Li and K withdrawal rates and erythrocytic balance Na-Na exchange rate constant to intracellular Ca concentration was investigated. Intracellular Ca concentration was modified by means of Ca-ionophore A 23187 and Ca-EGTA [ethyleneglycol bis[B-aminoethylether]-N,N''-tetraacetic acid]buffer. Hypertensive patients showed no differences in erythrocyte membrane electric potential, as determined by distribution. Only 2 systems of univalent cations transport were shown to be dependent on the intracellular Ca concentration: Ca increase was accompanied by the opening of K+-channels and the inhibition of erythrocyte membrane Na-K-ATPase. Increased rate of Ca withdrawal from erythrocytes of patients with essential hypertension and spontaneously-hypertensive rats under the effect of Ca-ionophore and moderate Ca2+ concentrations was due to an insufficiency of the cell''s Ca-pump rather than disorders in the properties of K+-channels. No significant Ca effect on passive transmembrane ion diffusion, Na, K-cotransport and Na-Na (Na-Li)-countertransport could be demonstrated.