Linked Life Data

20660818

Source:http://linkedlifedata.com/resource/pubmed/id/20660818

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-9-16
pubmed:abstractText
Previous studies in ovine uterine arteries have demonstrated that sex steroid hormones upregulate extracellular signal-regulated kinase 1/2 expression and downregulate the protein kinase C signaling pathway, resulting in the attenuated myogenic tone in pregnancy. The present study tested the hypothesis that chronic hypoxia during gestation inhibits the sex steroid-mediated adaptation of extracellular signal-regulated kinase 1/2 and protein kinase C signaling pathways and increases the myogenic tone of uterine arteries. Uterine arteries were isolated from nonpregnant and near-term pregnant sheep that had been maintained at sea level (?300 m) or exposed to high-altitude (3801 m) hypoxia for 110 days. In contrast to the previous findings in normoxic animals, 17?-estradiol and progesterone failed to suppress protein kinase C-induced contractions and the pressure-induced myogenic tone in uterine arteries from hypoxic animals. Western analyses showed that the sex steroids lost their effects on extracellular signal-regulated kinase 1/2 expression and phospho- extracellular signal-regulated kinase 1/2 levels, as well as the activation of protein kinase C isozymes in uterine arteries of hypoxic ewes. In normoxic animals, pregnancy and the sex steroid treatments significantly increased uterine artery estrogen receptor-? and progesterone receptor B expression. Chronic hypoxia selectively downregulated estrogen receptor-? expression in uterine arteries of pregnant animals and eliminated the upregulation of estrogen receptor-? in pregnancy or by the steroid treatments observed in normoxic animals. The results demonstrate that, in the ovine uterine artery, chronic hypoxia in pregnancy inhibits the sex steroid hormone-mediated adaptation of decreased myogenic tone by downregulating estrogen receptor-? expression, providing a mechanism linking hypoxia and maladaptation of uteroplacental circulation and an increased risk of preeclampsia in pregnancy.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1524-4563
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
750-7
pubmed:dateRevised
2011-10-3
pubmed:meshHeading
pubmed-meshheading:20660818-Animals, pubmed-meshheading:20660818-Anoxia, pubmed-meshheading:20660818-Blotting, Western, pubmed-meshheading:20660818-Chronic Disease, pubmed-meshheading:20660818-Estradiol, pubmed-meshheading:20660818-Estrogen Receptor alpha, pubmed-meshheading:20660818-Estrogen Receptor beta, pubmed-meshheading:20660818-Female, pubmed-meshheading:20660818-Gene Expression, pubmed-meshheading:20660818-Gonadal Steroid Hormones, pubmed-meshheading:20660818-Mitogen-Activated Protein Kinase 1, pubmed-meshheading:20660818-Mitogen-Activated Protein Kinase 3, pubmed-meshheading:20660818-Phosphorylation, pubmed-meshheading:20660818-Pregnancy, pubmed-meshheading:20660818-Progesterone, pubmed-meshheading:20660818-Receptors, Progesterone, pubmed-meshheading:20660818-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:20660818-Sheep, pubmed-meshheading:20660818-Uterine Artery, pubmed-meshheading:20660818-Vasoconstriction
pubmed:year
2010
pubmed:articleTitle
Chronic hypoxia inhibits sex steroid hormone-mediated attenuation of ovine uterine arterial myogenic tone in pregnancy.
pubmed:affiliation
Center for Perinatal Biology, Department of Physiology and Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural