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Chronic hypoxia increases fetoplacental vascular resistance and vasoconstrictor reactivity in the rat

, : Chronic hypoxia increases fetoplacental vascular resistance and vasoconstrictor reactivity in the rat. American Journal of Physiology. Heart and Circulatory Physiology 294(4): H1638-H1644

An increase in fetoplacental vascular resistance caused by hypoxia is considered one of the key factors of placental hypoperfusion and fetal undernutrition leading to intrauterine growth restriction (IUGR), one of the serious problems in current neonatology. However, although acute hypoxia has been shown to cause fetoplacental vasoconstriction, the effects of more sustained hypoxic exposure are unknown. This study was designed to test the hypothesis that chronic hypoxia elicits elevations in fetoplacental resistance, that this effect is not completely reversible by acute reoxygenation, and that it is accompanied by increased acute vasoconstrictor reactivity of the fetoplacental vasculature. We measured fetoplacental vascular resistance as well as acute vasoconstrictor reactivity in isolated perfused placentae from rats exposed to hypoxia (10% O(2)) during the last week of a 3-wk pregnancy. We found that chronic hypoxia shifted the relationship between perfusion pressure and flow rate toward higher pressure values (by approximately 20%). This increased vascular resistance was refractory to a high dose of sodium nitroprusside, implying the involvement of other factors than increased vascular tone. Chronic hypoxia also increased vasoconstrictor responses to angiotensin II (by approximately 75%) and to acute hypoxic challenges (by >150%). We conclude that chronic prenatal hypoxia causes a sustained elevation of fetoplacental vascular resistance and vasoconstrictor reactivity that are likely to produce placental hypoperfusion and fetal undernutrition in vivo.


PMID: 18310520

DOI: 10.1152/ajpheart.01120.2007

Other references

Gowrie, M.N., 2003: Environmental vulnerability index for the island of Tobago, West Indies. This study investigated the environmental vulnerability index (EVI) for the island of Tobago. Based on the EVI study developed by the South Pacific Applied Geosciences Commission (SOPAC), the vulnerability index was determined for anthropogenic, m...

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Nigam, S.; Müller, S.; Benedetto, C., 1989: Elevated plasma levels of platelet-activating factor (PAF) in breast cancer patients with hypercalcemia. Peripheral plasma concentrations of PAF were measured in patients with benign and malignant tumors of the breast, and in healthy female controls with a very sensitive PAF assay. The mean values +/- SEM were significantly higher in the malignant gr...

Mcevoy C.; Durand M.; Hewlett V., 1991: Spontaneous desaturations at two levels of oxygen saturation in infants with chronic lung disease cld. Pediatric Research 29(4 PART 2): 226A

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Timmons, R.G.; Siegel, J.S.; Metheny, R.S., 1971: Fatal pulmonary hemorrhage complicating infectious mononucleosis. Pennsylvania Medicine 74(5): 65-67

Kuz'min, V.P., 1979: Effect of peloid therapy on the state of cellular immunity in children with chronic tonsillitis. Voprosy Kurortologii, Fizioterapii, i Lechebnoi Fizicheskoi Kultury: 27-30

Erkanli, G.; Ercan, F.; Sirvanci, S.; Yananli, H.Raci.; Onat, F.; San, T., 2007: Time-dependent changes in distribution of basic fibroblast growth factor immunoreactive cells in rat hippocampus after status epilepticus. Objective: In this study, we aimed to examine time-dependent morphologic changes and quantitative alterations in the density of basic fibroblast growth factor (bFGF)-immunoreactive (ir) astrocytes and CA2 pyramidal neurons in dorsal hippocampus of...

Atkochyus V.B., 1982: The optimum conditions for negative and positive electro radiographic mammography. Biomedical Engineering (english Translation Of Meditsinskaya Tekhnika): 119-121

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