Sequential changes of extracellular matrix metalloproteins in pregnancy and labor in the rat chorio-allantois
Meraz-Cruz, N.Ã; Molina Delgado, G.; Vadillo-Ortega, F.
Revista de Investigacion Clinica; Organo del Hospital de Enfermedades de la Nutricion 55(1): 36-42
2003
ISSN/ISBN: 0034-8376 PMID: 12708162 Document Number: 559524
Participation of matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP) in the rupture of fetal membranes (FM) during labor has been proposed. We describe and characterize sequentially the activity of the enzymes that degrade connective tissue in the FM of the rat during pregnancy and labor. Pregnant Wistar rats were sacrificed on different days of gestation and samples of amniotic fluid (AF) and MCA were collected to be analyzed for proteolytic activity, zymography, western blot and northern blot. Results showed that during labor, there is a significant increase in the proteolytic activity in the MCA and in the AF. MMP-2 was identified from day 15 of pregnancy and it increased near labor. MMP-9 was only identified two days before labor. MMP-2 and MMP-9 mRNA expression were coincident with enzymatic activity and western blot data. During labor, TIMP-1 decreased and TIMP-2 did not change. These results allow us to conclude that there exists a quantitative and qualitative differential expression of MMPs during gestation, especially during labor.