Genetic background affects the biomechanical behavior of the postpartum mouse cervix.

摘要: Objective We hypothesized that the genetic makeup has an impact on functional behavior of uterine cervix. Therefore, we compared biomechanical properties cervix in postpartum 2 strains mice differ their underlying regenerative collagen remodeling characteristics: MRL/MpJ+/+ (MRL: high repair) and C57BL/6 (C57: low fibrotic repair). Study Design Cervical tensile proprieties were assessed day 3, 15, 60 MRL (n = 14) C57 13) (4-5 animals at each time point). Stress-strain curves generated using Shimadzu EZ-test instrumentation. tissue was stretched by 0.42 mm/min until rupture. Parameters viscoelasticity including slope (a measure stiffness), yield point (YP; moment when changes its from elastic to plastic), break (BP; strength) recorded analyzed blindly between strains. Data normalized weight 2-way analysis variance. Histological birefringence evaluation n=4; C57: n=4) performed 5 days after delivery. Results At 3 15 postpartum, cervices significantly more compliant than those ( P .02) rested a similar level (day 60: 26.1 ± 7.0 N/mm per gram; vs 15: .937). More force required reach YP 72.5 14.7 MRL: 19.9 1.6 N/g; .120) or 143.4 26.5 164.5 18.7 .412). There significant decrease BP both with .856 for strain, .008 day). displayed less cervical control Conclusion provide evidence may have function. are differences stiffness compliance vary phenotype.