Rossdale P D, Pashen R L, Jeffcott L B
J Reprod Fertil Suppl. 1979(27):521-9.
The synthetic prostaglandin (PG) analogue fluprostenol was used to induce parturition in mares and its mode of action was investigated by measuring endocrine changes before and during the induction period. Progestagens and unconjugated oestrogens showed little change during the induction period, but two different patterns in plasma PGFM levels were observed. The first was seen when foaling occurred within 90 min of injection; PGFM levels rose soon after injection and peaked during the maximum expulsive stage of labour, thus resembling events during natural foaling. The second occurred when foaling took longer than 90 min, and in these mares PGFM levels rose at various times after injection and peaked well before the onset of the expulsive stage of labour. It is suggested that these differences reflect the hormonal readiness of the mares to foal. Other procedures, such as rupture of the allantochorion, and dilatation of the cervix and injection of fluprostenol into the allantois, produced no uterine activity and did not stimulate labour or PGFM release.
合成前列腺素（PG）类似物氟前列醇被用于诱导母马分娩，并通过测量诱导期前后的内分泌变化来研究其作用方式。在诱导期，孕激素和未结合的雌激素变化不大，但观察到血浆PGFM水平有两种不同模式。第一种情况是在注射后90分钟内产驹；PGFM水平在注射后很快上升，并在分娩的最大排出阶段达到峰值，因此类似于自然产驹时的情况。第二种情况是产驹时间超过90分钟，在这些母马中，PGFM水平在注射后的不同时间上升，并在分娩排出阶段开始前很久就达到峰值。有人认为，这些差异反映了母马产驹的激素准备状态。其他操作，如尿膜绒毛膜破裂、子宫颈扩张以及向尿囊中注射氟前列醇，均未引起子宫活动，也未刺激分娩或PGFM释放。
