Enhanced fibrinolytic activity during the course of hemodialysis.

In order to clarify the effect of hemodialysis (HD) on the fibrinolytic system, fibrinolytic activity was evaluated in 27 patients undergoing regular hemodialysis treatment (RDT) using new parameters including plasma alpha 2-plasmin inhibitor (alpha 2 PI), alpha 2-plasmin inhibitor-plasmin complex (alpha 2 PIC), cross-linked fibrin degradation products (XL-FDP), tissue plasminogen activator (t-PA) activity, t-PA antigen and plasminogen activator inhibitor-1 (PAI-1) antigen. Predialysis baseline levels of plasminogen and alpha 2PI activity in RDT patients were significantly lower and those of alpha 2PIC were significantly higher than normal control values. During a single HD session, alpha 2PIC exhibited a continuous, significant increase reaching about 180% of initial values by the end of HD. alpha 2PI activity was significantly decreased at the end of the HD, though there were no significant changes in plasminogen activity during HD. Predialysis baseline levels of XL-FDP in RDT patients were significantly higher than normal control values. No significant changes in XL-FDP were observed during HD. Both t-PA activity and t-PA antigen significantly increased during HD, and PAI-1 antigen significantly decreased during HD. Von Willebrand factor (vWF) antigen in plasma, which is regarded as reflecting a release reaction by vascular endothelial cells to certain stimuli, also significantly increased during HD. However, neither vWF antigen nor t-PA antigen was increased by heparin administration alone. The changes in alpha 2PI and alpha 2PIC levels suggest that fibrinolytic activity is slightly higher in RDT patients and is even higher during HD.(ABSTRACT TRUNCATED AT 250 WORDS)