Endothelin in maternal and umbilical cord blood in spontaneous labor and at elective cesarean delivery.
We measured endothelin-1, a potent vasoconstrictor peptide released by the vascular endothelium, in maternal, umbilical cord, and retroplacental blood plasma in cases of spontaneous and elective cesarean delivery. Mean (+/- standard error) endothelin-1 in the maternal plasma increased with advancing pregnancy, from 1.2 +/- 0.13 pmol/L at 32-34 weeks to 2.4 +/- 0.2 pmol/L at 38-41 weeks (P less than .01) and 3.4 +/- 0.3 pmol/L (P less than .02) during labor. Concentrations were significantly higher in umbilical cord plasma than in maternal venous plasma, and higher in the cord venous plasma after vaginal delivery (52.9 +/- 11.4 pmol/L) than after cesarean performed before the onset of labor (9.0 +/- 1.1 pmol/L) (P less than .001). In spontaneous labor, concentrations in the retroplacental blood plasma (23.3 +/- 4.5 pmol/L) were approximately ten times higher than those in the maternal peripheral blood. Levels in the umbilical cord and retroplacental blood plasma were the highest found so far in any physiologic condition, suggesting that an increased intrauterine release of endothelin-1 at delivery may promote constriction of the blood vessels in the umbilical cord and placental bed.
Häkkinen
L M
LM
Department of Obstetrics and Gynecology, University of Oulu, Finland.
Vuolteenaho
O J
OJ
Leppäluoto
J P
JP
Laatikainen
T J
TJ
D000328:Adult; D002585:Cesarean Section; D016232:Endothelins / Q000097:blood*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007743:Labor, Obstetric / Q000097:blood*; D011247:Pregnancy / Q000097:blood*
D016232:Endothelins