Ajne G, Ahlborg G, Wolff K, Nisell H
Department of Obstetrics, Karolinska University Hospital Huddinge, Karolinska Institute, Stockholm, Sweden.
Am J Obstet Gynecol. 2005 Jul;193(1):234-40. doi: 10.1016/j.ajog.2004.11.023.
The aim of this study was to determine the physiologic role for endogenous endothelin in the regulation of vascular tone during normal pregnancy and preeclampsia. The vascular sensitivity to endothelin-1 during pregnancy was studied also.
Forearm blood flow was measured by venous occlusion plethysmography during intra-arterial infusion of phosphoramidon, an endothelin-converting enzyme inhibitor, for 60 minutes, which was followed by co-infusion with endothelin-1 for 30 minutes. Three groups were studied: healthy nonpregnant women, normal pregnant women, and women with preeclampsia.
There was a significant increase in forearm blood flow in the nonpregnant group after phosphoramidon infusion alone (73%+/-37%; P<.05). Phosphoramidon did not change forearm blood flow in pregnant subjects. Co-infusion with endothelin-1 significantly decreased forearm blood flow in both the nonpregnant and normal pregnant women (53%+/-7% and 40%+/-11%, respectively; P<.01). No response to endothelin-1 was found among women with preeclampsia.
The vascular sensitivity to endothelin-1 is not altered during normal pregnancy in contrast to preeclamptic pregnancy, where no effect of endothelin-1 was seen. Reduced endothelin dependence during pregnancy might be one mechanism behind the fall in peripheral vascular resistance.
本研究旨在确定内源性内皮素在正常妊娠和子痫前期血管张力调节中的生理作用。同时也研究了孕期血管对内皮素-1的敏感性。
通过静脉阻断体积描记法测量前臂血流量，在动脉内输注内皮素转换酶抑制剂磷酰胺60分钟，随后与内皮素-1共同输注30分钟。研究了三组对象：健康未孕女性、正常孕妇和子痫前期女性。
仅输注磷酰胺后，未孕组前臂血流量显著增加（73%±37%；P<0.05）。磷酰胺未改变孕妇的前臂血流量。与内皮素-1共同输注显著降低了未孕和正常孕妇的前臂血流量（分别为53%±7%和40%±11%；P<0.01）。子痫前期女性对内皮素-1无反应。
与子痫前期妊娠中未观察到内皮素-1的作用不同，正常妊娠期间血管对内皮素-1的敏感性未改变。孕期内皮素依赖性降低可能是外周血管阻力下降的一种机制。
