Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-8-25
pubmed:abstractText
Tissue factor pathway inhibitor (TFPI) is a multivalent Kunitz-type proteinase inhibitor that directly inhibits factor Xa and, in a factor Xa-dependent fashion, produces feedback inhibition of the factor VIIa/TF catalytic complex responsible for the initiation of coagulation. To further define the physiologic role of TFPI, gene-targeting techniques were used to disrupt exon 4 of the TFPI gene in mice. This exon encodes Kunitz domain-1 of TFPI, which is required for factor VIIa/TF inhibition. In mice heterozygous for TFPI gene-disruption, TFPI(K1)(+/-), an altered form of TFPI lacking Kunitz domain-1, circulates in plasma at a concentration approximately 40% that of wild-type TFPI. TFPI(K1)(+/-) animals have plasma TFPI activity approximately 50% that of wild-type mice, based on a functional assay that measures factor VIIa/TF inhibition, and have a normal phenotype. Sixty percent of TFPI(K1)(-/-) mice die between embryonic days E9.5 and E11.5 with signs of yolk sac hemorrhage. The extent of structural abnormalities within the yolk sac vascular system appears to mirror the condition of the embryo, suggesting that the embryonic and extra-embryonic tissues are both responding to same insult, presumably circulatory insufficiency. Organogenesis is normal in TFPI(K1) null animals that progress beyond E11.5, but hemorrhage, particularly in the central nervous system and tail, is evident during later gestation and none of the TFPI(K1)(-/-) mice survive to the neonatal period. The presence of immunoreactive fibrin(ogen) in the liver and intravascular thrombi is consistent with the notion that unregulated factor VIIa/TF action and a consequent consumptive coagulopathy underlies the bleeding diathesis in these older embryos. Human TFPI-deficient embryos may suffer a similar fate because an individual with TFPI deficiency has not been identified.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
944-51
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:9242522-Abnormalities, Multiple, pubmed-meshheading:9242522-Animals, pubmed-meshheading:9242522-Blood Vessels, pubmed-meshheading:9242522-Central Nervous System, pubmed-meshheading:9242522-Disseminated Intravascular Coagulation, pubmed-meshheading:9242522-Embryonic and Fetal Development, pubmed-meshheading:9242522-Exons, pubmed-meshheading:9242522-Factor VIIa, pubmed-meshheading:9242522-Factor Xa, pubmed-meshheading:9242522-Female, pubmed-meshheading:9242522-Fetal Death, pubmed-meshheading:9242522-Fetal Diseases, pubmed-meshheading:9242522-Genes, Lethal, pubmed-meshheading:9242522-Genotype, pubmed-meshheading:9242522-Gestational Age, pubmed-meshheading:9242522-Hemorrhagic Disorders, pubmed-meshheading:9242522-Humans, pubmed-meshheading:9242522-Lipoproteins, pubmed-meshheading:9242522-Male, pubmed-meshheading:9242522-Mice, pubmed-meshheading:9242522-Mice, Knockout, pubmed-meshheading:9242522-Morphogenesis, pubmed-meshheading:9242522-Tail, pubmed-meshheading:9242522-Yolk Sac
pubmed:year
1997
pubmed:articleTitle
Tissue factor pathway inhibitor gene disruption produces intrauterine lethality in mice.
pubmed:affiliation
Division of Hematology, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO 63110, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.