PLASMINOGEN ACTIVATORS IN ECTOPIC AND UTERINE ENDOMETRIUM

Objective: To investigate the expression of the plasminogen activator (PA)-plasmin system components in ectopic endometrium and in uterine e ndometrium from women with and without endometriosis. Design: Plasmino gen, PAs (urokinase and tissue plasminogen activator), and PA inhibito rs (1 and 2) were detected by immunohistochemistry using a alkaline ph osphatase staining method. Results: No differences in staining were fo und between uterine endometrium of women with endometriosis and women without endometriosis with any of the antibodies used. However, we did find differences between uterine and ectopic endometrium. Although th e expression of the components of the PA-plasmin system reflected the cyclic changes in the hormonal levels in uterine endometrium, ectopic endometrium maintained a very high level of plasminogen and urokinase in every sample. We were unable to detect the presence of PA inhibitor s in either uterine or ectopic endometrium. Conclusions: There is no e vidence that uterine endometrium from women with endometriosis is orig inally more able to implant than that of women without the disease bec ause of an increase in their PA expression. The high levels of urokina se and plasminogen in ectopic endometrium may reflect a more invasive nature of the endometriotic implants in the peritoneal cavity.