RELATION BETWEEN THE OSMOLALITY TREND AND ORNITHYNEDECARBOXYLASE ACTIVITY IN RED-BLOOD-CELLS OF UREMIC PATIENTS DURING HEMODIALYTIC TREATMENT

In uremic patients during chronic hemodialysis an increase in the volu me of red blood cells is observed. Contemporaneously there is an incre ase in intraerythrocytic ornithynedecarboxylase activity beyond the no rmal content (P < 0.01), a high level of seric and plasmatic polyamine s (P < 0.01) and a decrease in seric osmolality (P < 0.01) with pH imp rovement. The trends of osmolality, ornithynedecarboxylase, mean cell volume and pH are significantly related. Our data support the hypothes is that, during hemodialysis, red blood cell volume changes and increa sed ornithynedecarboxylase activity are dependent on the general impro vement of plasma tonicity. Moreover, the absence of inhibition of orni thynedecarboxylase activity by high levels of putrescine is noted. (C) 1998 Elsevier, Paris.