title: Complete antithrombin deficiency in mice results in embryonic lethality.
abstract: Antithrombin is a plasma protease inhibitor that inhibits thrombin and contributes to the maintenance of blood fluidity. Using targeted gene disruption, we investigated the role of antithrombin in embryogenesis. Mating mice heterozygous for antithrombin gene (ATIII) disruption, ATIII(+/-), yielded the expected Mendelian distribution of genotypes until 14.5 gestational days (gd). However, approximately 70% of the ATIII(-/-) embryos at 15.5 gd and 100% at 16.5 gd had died and showed extensive subcutaneous hemorrhage. Histological examination of those embryos revealed extensive fibrin(ogen) deposition in the myocardium and liver, but not in the brain or lung. Furthermore, no apparent fibrin(ogen) deposition was detected in the extensive hemorrhagic region, suggesting that fibrinogen might be decreased due to consumptive coagulopathy and/or liver dysfunction. These findings suggest that antithrombin is essential for embryonic survival and that it plays an important role in regulation of blood coagulation in the myocardium and liver.
authors.affiliation: First Department of Internal Medicine, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ishiguro
authors.forename: T
authors.initials: T
authors.lastname: Kojima
authors.forename: K
authors.initials: K
authors.lastname: Kadomatsu
authors.forename: Y
authors.initials: Y
authors.lastname: Nakayama
authors.forename: A
authors.initials: A
authors.lastname: Takagi
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: N
authors.initials: N
authors.lastname: Takeda
authors.forename: M
authors.initials: M
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Matsushita
authors.forename: K
authors.initials: K
authors.lastname: Kusugami
authors.forename: T
authors.initials: T
authors.lastname: Muramatsu
authors.forename: H
authors.initials: H
authors.lastname: Saito
mesh_terms: D000818:Animals; D000990:Antithrombin III / Q000235:genetics; D020152:Antithrombin III Deficiency / Q000401:mortality*; D003433:Crosses, Genetic; D020964:Embryo Loss; D018390:Gene Targeting; D005804:Genes, Lethal; D006579:Heterozygote; D006720:Homozygote; D051379:Mice; D008817:Mice, Mutant Strains; D015842:Serine Proteinase Inhibitors / Q000172:deficiency*
chemical_list: D015842:Serine Proteinase Inhibitors; D000990:Antithrombin III