Fitzpatrick R J
Ciba Found Symp. 1977(47):31-47. doi: 10.1002/9780470720295.ch3.
Dilatation of the cervix at parturition necessitates changes in the physical characteristics of cervical collagen and glycosaminoglycans which are probably hormone-dependent. The infusion of prostaglandin F2alpha (PGF2alpha) into the arterial blood supply to uterus and cervix of sheep pregnant for about 125 days resulted in cervical dilatation after 24 hours but this response was inconsistent; one factor affecting the response appeared to be the progesterone status, low circulating progesterone being associated with dilatation. Preliminary experiments in goats in which pregnancy is terminated by removal of the corpora lutea at day 125, subject to modification by the administration of progesterone, indomethacin or PGF2alpha, support the view that PGF2alpha evokes softening and dilatation of the cervix but that this is blocked by progesterone.
分娩时子宫颈的扩张需要子宫颈胶原蛋白和糖胺聚糖的物理特性发生变化，而这些变化可能依赖于激素。向怀孕约125天的绵羊子宫和子宫颈的动脉血液供应中注入前列腺素F2α（PGF2α），24小时后导致子宫颈扩张，但这种反应并不一致；影响反应的一个因素似乎是孕酮状态，循环孕酮水平低与子宫颈扩张有关。在山羊身上进行的初步实验中，在第125天通过切除黄体终止妊娠，并通过给予孕酮、吲哚美辛或PGF2α进行调整，支持了以下观点：PGF2α会引起子宫颈软化和扩张，但这一过程会被孕酮阻断。
