Cyclic nucleotides (cAMP and cGMP) are the main second messengers linked to vasodilatation. They are synthesized by cyclases and degraded by different types of phosphodiesterases (PDE). The effect of PDE inhibition and cyclases stimulation on 5-hydroxytryptamine (5-HT; 1 microM) and histamine (10 microM) contracted arteries was analysed. Stimulation of guanylate cyclase or adenylate cyclase rel...

Background: Arterial catheters are frequently needed to optimize the intensive care in sick newborn. Umbilical Catheters (UAC) is more popular than peripheral arterial catheterization. They utilized provide continuous accurate blood pressure monitoring, frequent assessment of gas exchange efficiency, sampling and rarely for transfusion. may be used emergencies infuse fluids or medications absen...

Background: To evaluate the effect of oxytocin on blood circulation of fetus and uterus by Doppler ultrasound. Materials and Methods: Forty six pregnant women were assigned to receive for indication of delivery intravenous oxytocin. Doppler velocitometry before and after administration of oxytocin for umbilical,middle cerebral artery and uterine artery were performed, and Pulsatility index (PI)...

Selenium (Se) can protect endothelial cells (EC) from oxidative damage by altering the expression of selenoproteins with antioxidant function such as cytoplasmic glutathione peroxidase (cyGPX), phospholipid hydroperoxide glutathione peroxidase (PHGPX) and thioredoxin reductase (TR). If the role of Se on EC function is to be studied, it is essential that a model system be chosen which reflects s...

Activation of cyclic nucleotide-dependent signaling pathways leads to relaxation of bovine carotid artery smooth muscle contractions and is associated with increased phosphorylation of the small heat shock-related protein (HSP20). Previous reports have shown that human umbilical artery smooth muscle is uniquely resistant to cyclic nucleotide-dependent relaxation, and HSP20 is not phosphorylated...

Background: Abnormal umbilical cord pH can be indicated a distress imposed of newborn and can also be useful in determining the prognosis of the newborn. There are different views about the effect of the neonatal delivery method on the blood gas analysis of the umbilical artery. This study aimed to determine the effect of the method of delivery on umbilical artery pH. Methods: In this Cross-Sec...

OBJECTIVE We aimed to evaluate ductus venosus Doppler waveforms before and after amniocentesis in order to investigate any effect of amniocentesis on fetal myocardial hemodynamics. We also evaluated the umbilical artery, uterine artery and fetal mid-cerebral artery Doppler waveforms in order to investigate any relationship with ductus venosus Doppler changes. METHODS The study population cons...

Background. This study investigated the effects of impairment to placental flow on flow patterns through the aortic isthmus because in the fetus, this vascular segment is the link between the parallel vascular systems perfused by the left and right ventricles. Methods and Results. A progressive increase in resistance to blood flow through the placenta was created in seven exteriorized fetal lam...

The whole blood concentrations of 22 amino acids were measured in a chronic, unstressed fetal lamb preparations. Samples were taken daily from the umbilical artery, umbilical vein, and maternal artery over the latter quarter of gestation. 73 sets of samples (from the umbilical artery and vein and the maternal artery) from 13 animals were analyzed for amino acid levels. Oxygen contents were dete...

This study was designed to evaluate the degree of placenta share discordance in relation to the betamethasone-induced return of positive end-diastolic flow in monochorionic twin pregnancies with selective intrauterine growth restriction (sIUGR) and abnormal umbilical artery Doppler. Monochorionic twins with sIUGR was defined as one twin having an estimated fetal weight below the 10th percentile...