Topographic analysis of gene expression for cervical Matrix Metalloproteinase-2 (MMP-2), Matrix Metalloproteinase-8 (MMP-8), and matrix metalloproteinase tissue inhibitor-1 (TIMP-1) enzymes by QF-PCR to determine the timing of parturition in rats

Delivery at term arises from the orderly, coordinated progression of physiological adaptations that occur across the reproductive system during gestation. Deviations in the development or timing of these adaptations can precipitate preterm birth or, conversely, prolong gestation into the postterm period. The cervix maintains pregnancy by remaining functionally closed and providing mechanical support for fetal retention; however, it must undergo extensive remodeling—encompassing softening, ripening, effacement, and dilation—for birth to occur. Cervical tissue is heterogeneous, comprising sparsely distributed stromal and immune cells within an extracellular matrix (ECM) dominated by connective tissue components. Because collagen (predominantly types I and III) is the most abundant ECM protein in the cervix, elucidating its turnover, cross-linking, and fibrillar organization across gestation is central to understanding the biomechanical transitions that govern the timing of parturition. In this study, twenty 90 day old, experimentally naïve female Wistar albino rats (Rattus norvegicus; 200–250 g) were included. Ten animals were examined at gestational day (GD) 15 and ten at GD20. For regional (topographical) analysis of the cervix, each specimen was dissected into the Portio Vaginalis and Portio Supravaginalis, which were analyzed as separate experimental regions. Expression levels of MMP 2, MMP 8, TIMP 1, and ACTB were quantified by quantitative fluorescence PCR (QF PCR), followed by statistical analysis. Relative MMP 2 expression in the Portio Vaginalis was 4.63 fold higher on gestational day 20 than on day 15 (p = 0.024), indicating statistically significant upregulation. These findings support a contributory role for MMP 2 in pregnancy associated cervical remodeling.