SOLUBLE P-SELECTIN IS RELEASED FROM ACTIVATED PLATELETS IN-VIVO DURING HEMODIALYSIS

During hemodialysis, platelets are activated across a dialyzer. Solubl e P-selectin (sP-selectin) is a form of P-selectin which is a glycopro tein relocated from secretory granules to the surfaces of platelets an d endothelial cells after these cells have been physiologically activa ted. To investigate whether sP-selectin is useful as a marker of plate let activation during hemodialysis, we measured the plasma concentrati on of sP-selectin by enzyme-linked immunosorbent assay in 6 patients h emodialyzed in our institute using regenerated cellulose (RC) membrane s and thereafter polysulfone membranes. Concomitantly, we also measure d the plasma concentration of platelet factor 4 and beta-thromboglobul in which are released from alpha-granules of activated platelets. Duri ng hemodialysis with RC membranes, the beta-thromboglobulin level was significantly increased 15 min (p < 0.05) and the sP-selectin level 15 (p < 0.05) and 180 min (p < 0.05) after initiation of dialysis on the venous side as compared with the arterial side of the hemodialyzer. D uring hemodialysis with polysulfone membranes, no significant variatio n in plasma beta-thromboglobulin and sP-selectin levels was detected, The platelet factor 4 level increased more significantly across a dial yzer 180 min after initiation of dialysis with RC than with polysulfon e membranes (p < 0.01). The changes in plasma platelet factor 4 and be ta-thromboglobulin levels demonstrated that platelets are more activat ed during hemodialysis with RC than with polysulfone membranes. The ch anges in plasma sP-selectin levels during hemodialysis with RC confirm that the release of P-selectin purely from activated platelets was de tected by enzyme-linked immunosorbent assay, sP-selectin may be a mark er of platelet activation during hemodialysis.