Effect of haemodialysate and its peptide fractions on lactate dehydrogenase activity in erythrocytes from healthy subjects and patients with end-stage renal disease.

The effect of haemodialysate and its 3 peptide fractions on lactate dehydrogenase activity in erythrocytes was studied in patients treated by repeated haemodialysis for end-stage renal disease and in healthy subjects. Erythrocytes from dialyzed patients showed significantly lower LDH activity than those from healthy subjects. After a 3-h incubation with haemodialysate (675 and 450 micrograms protein/ml), or its peptide fraction III (270 and 190 micrograms protein/ml), a significant inhibition of LDH activity was observed. On the other hand, neither haemodialysate nor its peptide fractions inhibited LDH activity in red blood cells from patients with end-stage renal disease treated by repeated haemodialysis.