Skip to main content

Expression of tissue type and urokinase type plasminogen activators as well as plasminogen activator inhibitor type-1 and type-2 in human and rhesus monkey placenta

  • ZHAO-YUAN HU (a1), YI-XUN LIU (a1), KUI LIU (a1) (a2), SIMON BYRNE (a3), TOR NY (a2), QIANG FENG (a3) and COLIN D. OCKLEFORD (a3)...
    • Published online: 01 February 1999

The distribution of mRNAs and antigens of tissue type (t) and urokinase type (u) plasminogen activators (PA) plus their corresponding inhibitors, type-1 (PAI-1) and type-2 (PAI-2) were studied in human and rhesus monkey placentae by in situ hybridisation and immunocytochemistry. Specific monkey cRNA and antibodies against human tPA, uPA, PAI-1 and PAI-2 were used as probes. The following results were obtained. (1) All the molecules tPA, uPA, PAI-1 and PAI-2 and their mRNAs were identified in the majority of the extravillous cytotrophoblast cells of the decidual layer between Rohr's and Nitabuch's striae and in cytotrophoblast cells of the chorionic plate, basal plate, intercotyledonary septae and cytotrophoblast cells of the chorionic villous tree. (2) Expression of uPA and PAI-2 was noted in villous trophoblast whereas tPA and PAI-1 were mainly concentrated where detachment from maternal tissue occurs. (3) No expression of tPA, uPA, PAI-1 and PAI-2 was observed in the basal plate endometrial stromal cells, chorionic plate connective tissue cells, septal endometrial stromal cells or villous core mesenchyme. (4) The distribution of probes observed following in situ hybridisation is generally consistent with the immunofluorescence pattern of the corresponding antigens and no significant interspecies differences were noted. It is possible that both decidual and extravillous trophoblast cells of placentae of human and rhesus monkey are capable of producing tPA, uPA, PAI-1 and PAI-2 to differing extents. Coordinated expression of these genes in the tissue may play an essential role in the maintenance of normal placentation and parturition. The differences in distribution we observed are consistent with the suggestion that coordinated expression of tPA and its inhibitor PAI-1 may play a key role in fibrinolytic activity in the early stages of placentation and separation of placenta from maternal tissue at term. On the other hand, uPA with its inhibitor PAI-2 appears mainly to play a role in degradation of trophoblast cell-associated extracellular matrix, and thus may be of greatest importance during early stages of placentation.

Corresponding author
Correspondence to Dr Colin Ockleford, Department of Pre-clinical Sciences, University of Leicester Medical School, Leicester LE1 9HN, UK.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

The Journal of Anatomy
  • ISSN: 0021-8782
  • EISSN: 1469-7580
  • URL: /core/journals/journal-of-anatomy
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Type Description Title

 PDF (796 KB)
796 KB


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed