TISSUE-PLASMINOGEN ACTIVATOR AND PLASMINOGEN-ACTIVATOR INHIBITORS OF TYPE-1 AND TYPE-2 IN THE PLASMA OF PARTURIENT WOMEN

Changes in the fibrinolytic system of parturient women have so far bee n only partially documented. Our main questions were whether and how t he concentration of tissue plasminogen activator (tPA) and plasminogen activator inhibitors of type 1 (PAI-1) and type 2 (PAI-2) change in t he plasma throughout normal labor. The study group consisted of 38 wom en with normal pregnancy, delivering at term. The concentration of ant igens tPA, PAI-1 and PAI-2 in plasma was tested by enzyme-linked immun o-sorbent assay method, and the activity of PAI-1 by plasmin method. R esults were analysed statistically. During labor the level of tPA anti gen increases over two times: from 9.3 +/- 4.3 ng/ml before labor, to 23.3 +/- 9.6 ng/ml in the second stage of labor. Changes of PAI-1 anti gen as well as its activity though noticeable, were not statistically significant. PAI-2 antigen level increased significantly in the third stage (146.3 +/- 58.7 ng/ml before labor, and 212.2 +/- 75.0 ng/ml aft er placenta expulsion). In summary the more significant change in the fibrinolytic system during labor is an increase of the level of tPA an d PAI-2 antigens, but their peaks appear in different stages of labor. The predominance of PAIs over tPA is maintained throughout the whole labor, though on a lower level as can be inferred from the tPA/PAIs ra tio.