Dhall K, Kumar M, Dhall G I, Jain P, Singh K T, Chakravorti R N
Ric Clin Lab. 1979 Jan-Mar;9(1):25-33. doi: 10.1007/BF02905024.
The vasopressor activity of human amniotic fluid was assessed in 46 primigravidas during the third trimester of pregnancy. The subjects included 20 normal and 26 cases of pregnancy toxaemia. For identification of the vasopressor activity of the amniotic fluid, blood pressure measurements were made in the intact rat, and the smooth muscle contraction of the rat ascending colon preparation was determined in vitro. The samples of amniotic fluid showing vasopressor activity were lyophilized and subjected to gel filtration using Sephadex G-100. The various fractions thus obtained were monitored at 280 nm and the pressor activity was re-estimated. It was observed that most of the pressor activity of the amniotic fluid of the toxaemic patients was capable of causing contraction of the rat colon as well as a significant rise in the systolic blood pressure of the intact rat. Furthermore, this activity was found to be heat-labile and was completely blocked by cinnarizine. Fractionation of the amniotic fluid showing vasopressor activity by gel filtration further substantiated the findings reported above. On the basis of these results it was concluded that the pressor activity of the amniotic fluid was due to the presence of an angiotensin II-like substance. Its concentration was found to be higher in the toxaemic group than in normotensive subjects.
在46例初产妇妊娠晚期评估了羊水的升压活性。受试者包括20例正常孕妇和26例妊娠中毒症患者。为了鉴定羊水的升压活性，对完整大鼠进行血压测量，并在体外测定大鼠升结肠标本的平滑肌收缩。将显示升压活性的羊水样本冻干，并用葡聚糖G - 100进行凝胶过滤。对由此获得的各种馏分在280 nm处进行监测，并重新评估其升压活性。观察到，妊娠中毒症患者羊水中的大部分升压活性能够引起大鼠结肠收缩以及完整大鼠收缩压显著升高。此外，发现这种活性对热不稳定，并被桂利嗪完全阻断。通过凝胶过滤对显示升压活性的羊水进行分级分离进一步证实了上述发现。基于这些结果得出结论，羊水的升压活性归因于一种类似血管紧张素II的物质的存在。发现其浓度在妊娠中毒症组中高于血压正常的受试者。
