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 fac tors may be responsible for the changes in vessel behavior that are postula ted to underlie the pathogenesis of preeclampsia. We wished to ascertain wh ether such changes in endothelial function are dependent on the vascular be d under investigation. STUDY DESIGN: Myometrial and infracolic omental vessels resistance vessels were obtained at cesarean delivery or hysterectomy. After incubation with e ither plasma from women with preeclampsia or plasma from normotensive pregn ant women, myographic techniques were used to assess the endothelium-depend ent relaxations of these vessels. RESULTS: Incubation of myometrial vessels from normotensive pregnant women with plasma from women with preeclampsia resulted in a significant reductio n in endothelium-dependent relaxation, an effect that was independent of th e parity of the patients from whom the vessels had been taken. Incubation o f omental vessels from normotensive pregnant women and myometrial vessels f rom nonpregnant women with plasma from women with preeclampsia had no effec t on the endothelium-dependent relaxation observed. CONCLUSIONS: This study demonstrates that the inducible changes in resistan ce vessel behavior are dependent on the tissue bed under investigation and on the pregnancy status of the patient.