Umbilical artery

The initial component of the PTX-induced contraction is selectively inhibited by ouabain, whereas the second component is rather potentiated by it (77). A similar inhibitory effect of ouabain on the contractile response to PTX is observed in the umbilical artery, which is devoid of adrenergic innervation 18). 

Nair, X. Contractile responses of guinea pig umbilical arteries to various hallucinogenic agents. Res Commun Chem Pathol Pharmacol 9 535-542, 1974. 

Examine liver, gallbladder (mouse), stomach, spleen, pancreas, intestines, kidneys, adrenal gland, ureters, bladder, umbilical artery, genital organs, dorsal aorta, and caudal vena cava. Possible abnormalities that can be observed include absent renal papilla, dilated ureter(s), and displaced testis. 

I have never understood the reasons that there might be connection between the twitching of a umbilical artery in a sheep and the appearance of an insight in the mind of man. And, I have never personally met this pharmacologist. Some day, 1 hope to do both. 

The transfection data summarized in Fig. 13 were obtained with primary human umbilical artery endothelial cells (HUAEC). Vascular endothelial cells, acting as an interface between circulating blood and tissues, are known to be involved in inflammatory processes, in atherosclerosis and angiogenesis, and represent a remarkable challenge as a gene therapy target. Their therapy with nonviral vectors... 

Day HE, Campeau S, Watson SJ, Jr., Akil H (1997) Distribution of ocia-, ocib- anspinal cord. Journal of chemical neuroanatomy 13 115-39 Dennedy MC, Houlihan DD, McMillan H, Morrison JJ (2002) (J2- and (J3-adrenoreceptor ago-nists human myometrial selectivity and effects on umbilical artery tone. Am J Obstet Gynecol... 

Ruhle W, Graf Von Ballestrem CL, Pult HM, Gnirs J (1995) [Correlation of cotinine levels in amniotic fluid, umbilical arterial blood and maternal blood.] Geburtshilfe Frauenheilkd, 55 156-159 (in German). 

Two umbilical arteries from the foetus carry blood to the placenta and a single umbilical vein returns blood from the placenta back to the foetus. The functions of the placenta in pregnancy are to supply oxygen and nutrients from the maternal circulation to the foetus and to remove waste materials, such as urea and carbon dioxide, from foetal blood. 

Kashiwagi M, Chaoui R, Stallmach T, Hurlimann S, Lauper U, Hebisch G. Fetal bilateral renal agenesis, pho-comelia, and single umbilical artery associated with cocaine abuse in early pregnancy. Birth Defects Res Part A Clin Mol Teratol 2003 67 951-2. 

DiGrande A, Malatino LS, Boura ALA, Read MA, Walters WAW. Modulation by adenosine of thromboxane Aj receptor-mediated constriction in the human umbilical artery. Int J Clin armacol Ther Toxicol 1994 32 344-6... 

Esoolar G, Garrido M, Aznar-Salatti J, Ordinas A, Bastida E Con >arison between human umbilical artery and rabbit abdominal aorta as substrata for platdet adhesion and platelet thrombus fi>nnation under flow conditions Blood Vessels 28 520-531,1991. 

Heparinization of the fluid infused through an umbilical arterial catheter with heparin 0.25 units/ml reduces the likelihood of catheter occlusion heparinization of flushes without heparinizing the infusate is ineffective (20). 

Barrington KJ. Umbilical artery catheters in the newborn effects of catheter materials (Cochrane Review). In The Cochrane Library. 1st ed. Oxford Update Software, 1999. 

The hemodynamic effects of ritodrine have been assessed in 12 fetuses by cardiac and extracardiac Doppler sonography (1). Ritodrine significantly increased maternal and fetal heart rates, left cardiac stroke volume, and cardiac output. There was also an increase in the pulsatility index of the middle cerebral artery and a fall in the pulsatility index of the umbilical artery during ritodrine infusion. The authors suggested that ritodrine vasodilates fetal vessels in the placenta. 

Dennedy MC, Houlihan DD, McMillan H, Morrison JJ. p2- and p3-adrenoreceptor agonists human myometrial selectivity and effects on umbilical artery tone. Am J Obstet Gynecol 2002 187 641-647. 

Aguayo, C., Flores, C., Parodi, J., Rojas, R., Mann, G.E., Pearson, J.D., and Sobrevia, L. (2001) Modulation of adenosine transport by insulin in human umbilical artery smooth muscle ceUs from normal or gestational diabetic pregnancies. The Journal of Physiology, 534 (Pt 1), 243-254. 

Watanabe et al. (1992) sequenced chemically the LC20 of porcine aorta myosin. There was only one amino acid substitution compared with chicken gizzard and two substitutions compared with human umbilical artery smooth muscle LC20. It is noteworthy that the substitutions never take place at positions 18 and 19, the phosphorylation sites for MLCK, or at positions 1, 2, and 9, the phosphorylation sites for PKC. 

In the placenta a volume of oxygen sufficient for fetal needs must diffuse across the membranes from maternal to fetal blood during the short time the two circulations are in close contact. This oxygen transfer is a function of several factors which include uterine and umbilical arterial 02 partial pressures, maternal and fetal placental blood flow rates, the 02 capacity and 02 affinity of maternal and fetal hemoglobin, the diffusing capacity of the placenta, the amount of C02 exchanged, and the vascular arrangement of maternal to fetal vessels. 

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