COMPARISON OF 2 FLUORESCENT-PROBES FOR THE MEASUREMENT OF ERYTHROCYTE-MEMBRANE FLUIDITY IN RENAL DIALYSIS PATIENTS

Two fluorescent probes were used for the measurement of membrane fluid ity in patients on haemodialysis and continuous ambulatory peritoneal dialysis. 1,6-Diphenyl-1,3,5-hexatriene (DPH) anisotropy gives an indi cation of lipid order and pyrene measures lateral diffusion through th e membrane, Pyrene dimer/monomer ratio was significantly lower than co ntrols in both pre-dialysis and post-dialysis samples but DPH anisotro py was unchanged. Both methods showed an increase in membrane fluidity across a 4 hour haemodialysis session. There was an increase in membr ane fluidity in CAPD patient samples which was more marked using DPH t han pyrene. These results suggest that the two probes give different b ut complementary information about changes in membrane fluidity and ma y be more informative when used together rather than singly.