THE PRODUCTION OF PLATELET-ACTIVATING-FACTOR (PAF) DURING HEMODIALYSIS WITH CUPROPHANE MEMBRANE - DOES THE CALCIUM-CONCENTRATION IN THE DIALYSATE PLAY ANY ROLE ON IT

There is evidence that PAF may be produced during hemodialysis (HD) ma inly when using cuprophane membrane (CU). It is also known that PAF pr oduction is dependent on the amount of extracellular calcium (E(Ca)(2)). In the present study, we investigated the production of PAF during HD with CU as well as the role of the Ca2+ in the dialysate with resp ect to PAF production. Five hemodialyzed patients were studied in two consecutive HD sessions (the first performed using dialysate without C a2+. and the second with a Ca2+ concentration of 3.25 mEq/L) and at di fferent times during the sessions the circulating PAF levels as well a s the leukocyte and platelet counts were measured. The results demonst rated that a) PAF was indeed produced during HD with CU, b) the highes t PAF levels in blood were observed between 5 and 15 minutes from the beginning of HD, at which time the lowest circulating leukocyte and pl atelet count were measured and c) PAF levels in blood were inversely p roportional to the Ca2+ concentration in the dialysate (with the excep tional case of the 15 minutes), although we expected the opposite resu lts.