Expression of matrix metalloproteinases-9 and tissue inhibitor of metalloproteinases-1 in placenta in normal pregnancy and patients with severe pregnancy induced hypertension

Objective: To study the expression of matrix metalloproteinases-9(MMP-9) and tissue inhibitor of metalloproteinases-1(TIMP-1) in placenta from patients with severe pregnancy induced hypertension(PIH). Methods: MMP-9 and TIMP-1 of placenta were determined by immunohistological method and compared between normal pregnancy (42 cases) and pregnancies accompanied by PIH (42 cases). Results:MMP-9 and TIMP-1 were located on trophoblast, endothelial cell of blood and villous strome. The level of MMP-9 was significantly lower in PIH group than that in normal group (P0.01).But the expression of TIMP-1 in the placenta from the normal group and the PIH group was undifferentiated (P0.05). Conclusion:The decrease of MMP-9 in the placenta from the severe PIH and the expression of TIMP-1 had no significant change in nomal placenta and the severe PIH’s placente. They may play a role in the cause of PIH.