RESPONSE OF FIBRINOLYTIC PROTEINS AND ENDOTHELIN-1 TO VENOUS OCCLUSION IN PATIENTS ON CHRONIC-HEMODIALYSIS

The main purpose of the present study was to determine whether any abn ormalities in the response of fibrinolytic activity to venous occlusio n could be observed in patients undergoing chronic hemodialysis (HD pa tients). A 10-min venous occlusion test was performed in 13 HD patient s and in 9 healthy subjects. The arm opposite to the arteriovenous fis tula was occluded in HD patients. The following factors were measured: tissue plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), plasmin-alpha 2-plasmin inhibitor complex (PIC), stabilized fibrin degradation product (D-dimer), and von Willebrand factor antig en determined by enzyme immunoassay, and endothelin 1 by radioimmunoas say with two antibodies. Preocclusion levels of PIG, D-dimer, von Will ebrand factor, and endothelin 1 were significantly higher and those of t-PA significantly lower in HD patients than in controls. During the occlusion, there was a positive correlation between the percent change s in t-PA and von Willebrand factor and between those in von Willebran d factor and PIC. There was no correlation between percent and absolut e changes during the occlusion in endothelin 1 and those in t-PA, PAI- 1, PIC, D-dimer, or von Willebrand factor. There was no significant di fference between HD patients and controls as to the percent changes in hematocrit, t-PA, PIC, D-dimer and von Willebrand factor. HD patients demonstrated a significantly greater percent change in PAI-1 than con trols. The mechanism by which endothelin 1 is released in response to the occlusion appears to differ from that for t-PA, PAI-1, and von Wil lebrand factor. PAI-1 may be readily released in response to stimuli t o blood vessels in HD patients.