Effects of maternal and fetal plasma from toxemic patients on the vasomotility of the human umbilical artery.

Maternal and fetal plasmas from patients with specific hypertensive disease of pregnancy (SHDP) are shown to have a greater vasoconstrictive effect on perfused human unbilical artery than plasma from normal parturients. The vasomotility of isolated segments of artery was determined by measuring perfusion pressure at constant flow rate. The differences were demonstrable with plasmas and artery segments from the same parturients and also when plasma from patients with SHDP and arteries from normal parturients were used. These results, which show that plasmas from SHDP patients have a larger vasoconstrictive effect on human umbilical artery than normal plasma, support and extend the suggestion that there may be humoral mechanism which participates in the physiopathology of SHDP. This humoral factor can be detected with human umbilical artery from both normal and SHDP parturients.