Bradykinin (BK) and serotonin (5-HT) are vasoactive agents that significantly contribute to the normal functioning of fetoplacental blood flow, including modulation of smooth muscle tone in umbilical vein and arteries. Accordingly, umbilical artery is a crucial component of fetoplacental circulation with the vital function of providing suitable perfusion and nutrition for placenta. The aim of t...

BACKGROUND Umbilical artery catheters are often used in unwell neonates. Infection related to the use of these catheters may cause significant morbidity and mortality. The use of prophylactic antibiotics has been advocated for all newborns with umbilical artery catheters in order to reduce the risk of colonisation and acquired infection. Countering this is the possibility that harm, such as the...

The vasoactive effects of oxidative stress induced by hydrogen peroxide (H2O2) on human umbilical artery strips as well as the possible mechanisms involved are studied. Contraction responses to cumulative H2O2 (10 M 3 × 10 M) in endothelium intact and denuded umbilical arteries and responses to cumulative H2O2 after incubation with L-NAME (10 M) (n = 8), indomethacin (10 M) (n = 8) and verapami...

Calcitonin gene-related peptide (CGRP), one of the most potent endogenous vasodilators known, has been implicated in vascular adaptations and placental functions during pregnancy. The present study was designed to examine the existence of CGRP-A receptor components, the calcitonin receptor-like receptor (CRLR) and receptor activity-modifying protein 1 (RAMP1), in the human placenta and the vaso...

Umbilical artery\vein, middle cerebral artery, and ductus venosus Doppler velocimetry were performed at 33 weeks of gestation in the settings of an intrauterine growth restricted fetus during a heart rate deceleration. Interestingly, we recorded a sudden onset redistribution of fetal blood flow with fetal bradycardia. Spontaneous normalization of waveforms was observed once fetal heart rate ret...

1. The aim of this study was to define from umbilical artery flow velocity waveforms absolute peak systolic and time-averaged velocity, fetal heart rate, fetal heart rate variability and flow velocity variability, and the relation between fetal heart rate and velocity variables in early pregnancy.2.A total of 108 women presenting with a normal pregnancy from 10 to 20 weeks of gestation consente...