ACTIVITY OF 72-KDA AND 92-KDA MATRIX METALLOPROTEINASES IN PLACENTAL TISSUES OF COWS WITH AND WITHOUT RETAINED FETAL MEMBRANES

This study compared the activity of matrix metalloproteinases (MMP-2 a nd MMP-9) in retained and non-retained bovine placenta. The activities of MMPs and their zymogens were measured in fetal and maternal placen tal tissues from control cows (group B) and animals affected with rete ntion of fetal membranes (group A) using a zymography technique on 10 per cent SDS polyacrylamide gels. The activity of proMMP-9 detected on ly in the maternal part of the placenta was lower in group A than in g roup B. ProMMP-2 activity was higher in group A than in group B in bot h tissues. The active forms of MMP-2 were observed in the maternal and fetal part of placenta in group B, but only the 68-kDa form was detec ted in the placental tissues of group A. The differences in enzyme act ivity between the groups and the lack of 64- and 60-kDa active forms o f MMP-2 in the maternal and fetal parts of the retained placenta may h ave influenced the hydrolysis of collagen and the proper release of fe tal membranes. (C) 1997 W. B. Saunders Company Ltd.