title: Endothelial nitric oxide synthase and nitric oxide regulate endothelial tissue factor expression in vivo in the sickle transgenic mouse.
abstract: Activation of the coagulation system is a characteristic feature of sickle cell anemia, which also includes clinical thrombosis. The sickle transgenic mouse abnormally expresses tissue factor (TF) on the pulmonary vein endothelium. Knowing that this aberrancy is stimulated by inflammation, we sought to determine whether nitric oxide (NO) contributes to regulation of endothelial TF expression in the sickle mouse model. We used the NY1DD sickle mouse, which exhibits a low-TF to high-TF phenotype switch on exposure to hypoxia/reoxygenation. Manipulations of NO biology, such as breathing NO or addition of arginine or L-NAME (N-nitro-L-arginine-methyl-ester) to the diet, caused significant modulations of TF expression. This was also seen in hBERK1 sickle mice, which have a different genetic background and already have high-TF even at ambient air. Study of NY1DD animals bred to overexpress endothelial nitric oxide synthase (eNOS; eNOS-Tg) or to have an eNOS knockout state (one eNOS(-/-) animal and several eNOS(+/-) animals) demonstrated that eNOS modulates endothelial TF expression in vivo by down-regulating it. Thus, the biodeficiency of NO characteristic of patients with sickle cell anemia may heighten risk for activation of the coagulation system.
authors.affiliation: Vascular Biology Center and Division of Hematology-Oncology-Transplantation, Department of Medicine, University of Minnesota Medical School, 420 Delaware Street SE, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Solovey
authors.forename: Rahn
authors.initials: R
authors.lastname: Kollander
authors.forename: Liming Chang
authors.initials: LC
authors.lastname: Milbauer
authors.forename: Fuad
authors.initials: F
authors.lastname: Abdulla
authors.forename: Yingie
authors.initials: Y
authors.lastname: Chen
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Kelm
authors.forename: Robert P
authors.initials: RP
authors.lastname: Hebbel
mesh_terms: D000755:Anemia, Sickle Cell / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009569:Nitric Oxide / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D013925:Thromboplastin / Q000378:metabolism*
chemical_list: D009569:Nitric Oxide; D013925:Thromboplastin; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse