Landgraf R, Schulz J, Eulenberger K, Wilhelm J
Exp Clin Endocrinol. 1983 May;81(3):321-8. doi: 10.1055/s-0029-1210243.
In cows, plasma oxytocin and vasopressin were determined by specific and sensitive radioimmunoassays before, during and after parturition. In no case, oxytocin is elevated until the forelimbs of the foetus were distending the vagina and presenting at the vulva, supporting the view that endogenous maternal oxytocin does not primarily induce parturition. This finding is confirmed by simultaneous recording of myometrial electrical activity in 3 animals. Maximal oxytocin levels of 60.4 to 116 pg/ml plasma were measured at delivery of the foetus. The elevation in plasma vasopressin (peak values at delivery: 4.74 to 41.5 pg/ml) might be due, at least partially, to the increase in plasma osmolality during parturition.
通过特异性和灵敏的放射免疫分析法测定奶牛分娩前、分娩期间及分娩后的血浆催产素和血管加压素水平。在胎儿前肢扩张阴道并露出外阴之前，催产素水平均未升高，这支持了内源性母体催产素并非主要引发分娩的观点。对3只动物子宫肌层电活动的同步记录证实了这一发现。在胎儿娩出时测得血浆催产素的最高水平为60.4至116皮克/毫升。血浆血管加压素升高（分娩时峰值：4.74至41.5皮克/毫升）可能至少部分归因于分娩期间血浆渗透压的升高。
