Petersen L K, Helmig R, Oxlund H, Vogel I, Uldbjerg N
Department of Obstetrics and Gynecology, Aarhus Kommunehospital, Denmark.
Eur J Obstet Gynecol Reprod Biol. 1994 Nov;57(2):123-8. doi: 10.1016/0028-2243(94)90054-x.
We examined the effect of human relaxin (hRLX-2) on the biomechanical properties of human fetal membranes in vitro. Intact chorioamniotic membranes were obtained from twelve elective cesarean sections before the onset of labor. Membrane strips with a fixed width were biomechanically tested after incubation for 20 h with hRLX-2 in concentrations of 10(-7) mol/l and 10(-9) mol/l. Incubation with hRLX-2 (10(-9) mol/l) changed the load-strain values as the membrane stiffness was decreased by 19% when compared with controls: median 2.45 N (range, 0.81-4.31) versus 3.03 N (1.28-5.46), P = 0.02 (Mann-Whitney test). For description of the membrane material as such, the stress-strain values were calculated by dividing the load-strain values with the cross sectional area of the membranes. Incubation with hRLX-2 (10(-9) mol/l) decreased the tensile strength of the membranes by 30%-0.817 N/mm2 (0.282-1.139) vs. 0.575 N/mm2 (0.101-1.150), P = 0.03--and reduced the elastic modulus by 31%--2.26 N/mm2 (0.82-5.08) versus 1.57 N/mm2 (0.51-3.71), P = 0.002. Less pronounced effects were found after incubation with hRLX (10(-7) mol/l). No quantitative or qualitative changes of the membrane collagen were found after relaxin incubation. Although the mechanism for rupture of the fetal membranes remains unknown, the present results suggest that relaxin might be involved in the process leading to rupture of the membranes.
我们在体外研究了人松弛素（hRLX - 2）对人胎膜生物力学特性的影响。在分娩发动前，从12例择期剖宫产中获取完整的羊膜绒毛膜。将宽度固定的膜条在浓度为10⁻⁷mol/L和10⁻⁹mol/L的hRLX - 2中孵育20小时后进行生物力学测试。与对照组相比，用hRLX - 2（10⁻⁹mol/L）孵育改变了负荷 - 应变值，膜硬度降低了19%：中位数为2.45N（范围0.81 - 4.31），而对照组为3.03N（1.28 - 5.46），P = 0.02（曼 - 惠特尼检验）。为描述膜材料本身，应力 - 应变值通过将负荷 - 应变值除以膜的横截面积来计算。用hRLX - 2（10⁻⁹mol/L）孵育使膜的抗张强度降低了30% - 0.817N/mm²（0.282 - 1.139），而对照组为0.575N/mm²（0.101 - 1.150），P = 0.03；并使弹性模量降低了31% - 2.26N/mm²（0.82 - 5.08），而对照组为1.57N/mm²（0.51 - 3.71），P = 0.002。用hRLX（10⁻⁷mol/L）孵育后发现的影响不太明显。松弛素孵育后未发现膜胶原蛋白的定量或定性变化。虽然胎膜破裂的机制尚不清楚，但目前的结果表明松弛素可能参与了导致胎膜破裂的过程。
