The effect of hemodialysis on the expression of platelet glycoproteins Ib, IIb/IIIa and P-selectin

To determine the effect of hemodialysis on expression of platelet receptors in patients with chronic renal failure. Design: Blood sampling performed in chronic HD patients prior to the dialysis session, then 15 and 180 minutes into HD. Both dialysis machine inlet and outlet samples were taken at 15 minutes. Control subjects had a single blood sample taken. Patients: Thirteen adult males on chronic hemodialysis and 20 age and sex matched healthy controls. Measurements: Flow-cytometric analysis of platelet GP-Ib,GP-IIb/IIIa, and P-selectin. Plasma vWF multimers were analyzed by SDS-polyacrylamide gel electrophoresis and immuno-blotting. Results: Mean channel fluorescence (MCF) for GP Ib was significantly (P < 0.05) decreased in pre-dialysis patients compared to controls and decreased further 3 hours into the dialysis session compared to the start of the dialysis treatment (P < 0.01). MCF for GP IIb/IIIa between predialysis patients and controls was similar, but decreased after a single dialysis session (P < 0.01). MCF for P-selectin on platelets was similar in patients and controls, but fewer platelets from the patients expressed P-selectin compared to controls (P < 0.05). Qualitative multimeric analysis of the vWF in patients, pre- and post-HD was unchanged. Conclusions: Alterations in platelet surface expression of GPIb, GPIIb/IIIa, and P-selectin may, partially contribute to the changes in platelet function seen in patients on hemodialysis. It is unlikely that alterations in the surface expression of these receptors alone can adequately account for the complex platelet and hemostatic changes associated with uremia and the HD procedure.