In vitro perfusion studies of single umbilical artery cords, the vasoactive effects of serotonin

To investigate the vascular resistance and the vasoactive effects of serotonin in arteries from single umbilical artery (SUA) cords. The preparations were sampled from 10 patients with SUA cords. The control group (n=20) was matched according to gestational age, birth weight percentile, blood pressure and proteinuria. The arterial segments were perfused in vitro employing a constant perfusion rate and measuring alterations in perfusion pressure. Following an initial test with serotonin 10(-7) M the drug was administrated in stepwise increasing concentrations from 10(-10) to 10(-5) M. The vascular resistance was significantly reduced in the SUA group compared to the control group (p