THE ORIGIN OF ENDOTHELIN-1 IN PATIENTS WITH SEVERE PREECLAMPSIA

Objective: To determine the site of origin of increased concentrations of plasma endothelin-l in patients with severe preeclampsia. Methods: Twelve patients with severe preeclampsia undergoing an indicated abdo minal delivery had endothelin-1 levels measured from plasma specimens drawn from right and left uterine and antecubital veins before deliver y and after placenta removal with uterine curettage. Twelve uncomplica ted control patients undergoing abdominal delivery had endothelin-1 co ncentrations drawn by an identical protocol. Clinical staff members we re blinded to endothelin-1 results and laboratory staff were blinded t o patient group assignment and sample source. Endothelin-1 plasma conc entrations were determined by radioimmunoassay and data were analyzed by paired t test. Results: No difference in endothelin-1 concentration was noted with respect to placental location, central versus peripher al, or predelivery versus postdelivery sampling procedures. Overall, p atients with preeclampsia had higher plasma concentrations of endothel in-1 (mean 11.0 +/- 6.6 pg/mL) compared with normotensive patients (me an 8.4 +/- 6.7 pg/mL, P < .005). Conclusion: The decidual-placental in terface does not appear to be the source of increased plasma endotheli n-1 concentrations found in severe preeclampsia. The origin of this in crease remains uncertain. (C) 1997 by The American College of Obstetri cians and Gynecologists.