Inducible change in the behavior of resistance arteries from circulating factor in preeclampsia: An effect specific to myometrial vessels from pregnant women

Objective: It has previously been observed that a circulating factor or factors may be responsible for the changes in vessel behavior that are postulated to underlie the pathogenesis of preeclampsia. We wished to ascertain whether such changes in endothelial function are dependent on the vascular bed under investigation. Study Design: Myometrial and infracolic omental vessels resistance vessels were obtained at cesarean delivery or hysterectomy. After incubation with either plasma from women with preeclampsia or plasma from normotensive pregnant women, myographic techniques were used to assess the endothelium-dependent relaxations of these vessels. Results: Incubation of myometrial vessels from normotensive pregnant women with plasma from women with preeclampsia resulted in a significant reduction in endothelium-dependent relaxation, an effect that was independent of the parity of the patients from whom the vessels had been taken. Incubation of omental vessels from normotensive pregnant women and myometrial vessels from nonpregnant women with plasma from women with preeclampsia had no effect on the endothelium-dependent relaxation observed. Conclusions: This study demonstrates that the inducible changes in resistance vessel behavior are dependent on the tissue bed under investigation and on the pregnancy status of the patient. (Am J Obstet Gynecol 2001;184:420-6.)