Rheological action of oxpentifylline and structurally related xanthine derivatives on human erythrocytes

Article type: Research Article

Authors: Bilto, Y.Y.^{a; b} | Player, M.^{a; b} | Stuart, J.^{a; b; *}

Affiliations: [a] Department of Haematology, Medical School, University of Birmingham, Birmingham 615 2TJ, U.K. | [b] Department of Biological Sciences, University of Jordan, Amman, Jordan

Correspondence: [*] Correspondence to Professor J. Stuart, Birmingham.

Note: [] Accepted by: Editor J.A. Dormandy

Abstract: Erythrocytes from healthy adults and patients with homozygous sickle cell anaemia were treated in vitro with either the calcium ionophore A23187, the K+ ionophore valinomycin, or the Na+/K+ ionophore nystatin to induce loss of intracellular K+ and water. The dehydrated cells showed loss of filterability (deformability) through pores of 5 µm diameter. Xanthine derivatives possessing one or two long side chains (oxpentifylline, torbafylline [HWA 448] and A81 3138) showed a similar protective effect against loss of filterability at concentrations of 1, 10 and 100 µmol/l and 5 mmol/l. Theophylline (1,3-dimethylxanthine) showed no protective effect at 5 mmol/l. The presence of at least one long side chain on the xanthine moiety seems to be an important determinant of rheological activity, possibly by increasing binding to the erythrocyte membrane.

Keywords: Rheology, Erythrocyte deformability, Ion transport

DOI: 10.3233/CH-1988-8210

Journal: Clinical Hemorheology and Microcirculation, vol. 8, no. 2, pp. 211-219, 1988