Uldbjerg N, Ulmsten U
Baillieres Clin Obstet Gynaecol. 1990 Jun;4(2):263-82. doi: 10.1016/s0950-3552(05)80226-3.
The mechanical properties of the human uterine cervix are determined mainly by the connective tissue component, whereas it is doubtful whether the scanty smooth muscle component is of any physiological importance. Histological and biochemical analyses reveal a fibrous connective tissue similar to that found in skin and tendon. Degradation of the collagen and an increase in some special dermatan sulphate proteoglycans can at least partly explain the pregnancy-associated softening of this connective tissue. Relatively high oestrogen levels seem to be an absolute condition for the process, even when it is induced pharmacologically. Treatment with progesterone-receptor blockers, PGE2, PGF2 alpha or relaxin in pregnancy induce cervical softening as well as histological and biochemical changes which cannot be distinguished from the physiological cervical softening which takes place in late pregnancy. Prostaglandins and relaxin might interact and could include cytokines such as interleukin-1 during the process. The effect of cervical tents cannot be explained only by the radial pressures they exert. Most probably stimulation of local prostaglandin synthesis is also involved.
人类子宫颈的力学特性主要由结缔组织成分决定，而少量的平滑肌成分是否具有任何生理重要性则值得怀疑。组织学和生化分析显示，其纤维结缔组织与皮肤和肌腱中的相似。胶原蛋白的降解以及某些特殊的硫酸皮肤素蛋白聚糖的增加至少可以部分解释这种结缔组织与妊娠相关的软化。相对较高的雌激素水平似乎是该过程的绝对条件，即使是通过药物诱导也是如此。在妊娠期间用孕激素受体阻滞剂、前列腺素E2、前列腺素F2α或松弛素进行治疗会导致宫颈软化以及组织学和生化变化，这些变化与妊娠晚期发生的生理性宫颈软化无法区分。前列腺素和松弛素可能相互作用，并且在此过程中可能涉及细胞因子，如白细胞介素-1。宫颈扩张器的作用不能仅通过它们施加的径向压力来解释。很可能还涉及局部前列腺素合成的刺激。
