title: Elucidation of the thromboregulatory role of CD39/ectoapyrase in the ischemic brain.
abstract: Endothelial CD39 metabolizes ADP released from activated platelets. Recombinant soluble human CD39 (solCD39) potently inhibited ex vivo platelet aggregation in response to ADP and reduced cerebral infarct volumes in mice following transient middle cerebral artery occlusion, even when given 3 hours after stroke. Postischemic platelet and fibrin deposition were decreased and perfusion increased without increasing intracerebral hemorrhage. In contrast, aspirin did not increase postischemic blood flow or reduce infarction volume, but did increase intracerebral hemorrhage. Mice lacking the enzymatically active extracellular portion of the CD39 molecule were generated by replacement of exons 4-6 (apyrase-conserved regions 2-4) with a PGKneo cassette. Although CD39 mRNA 3' of the neomycin cassette insertion site was detected, brains from these mice lacked both apyrase activity and CD39 immunoreactivity. Although their baseline phenotype, hematological profiles, and bleeding times were normal, cd39(-/-) mice exhibited increased cerebral infarct volumes and reduced postischemic perfusion. solCD39 reconstituted these mice, restoring postischemic cerebral perfusion and rescuing them from cerebral injury. These data demonstrate that CD39 exerts a protective thromboregulatory function in stroke.
authors.affiliation: Division of Cardiology, Department of Medicine, College of Physicians and Surgeons, Columbia University, Presbyterial Hospital 10 Stem, 630 W 168th Street, New York, NY 10032, USA. djp5@columbia.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Pinsky
authors.forename: M Johan
authors.initials: MJ
authors.lastname: Broekman
authors.forename: Jacques J
authors.initials: JJ
authors.lastname: Peschon
authors.forename: Kim L
authors.initials: KL
authors.lastname: Stocking
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Fujita
authors.forename: Ravichandran
authors.initials: R
authors.lastname: Ramasamy
authors.forename: E Sander
authors.initials: ES
authors.lastname: Connolly
authors.forename: Judy
authors.initials: J
authors.lastname: Huang
authors.forename: Szilard
authors.initials: S
authors.lastname: Kiss
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Tanvir F
authors.initials: TF
authors.lastname: Choudhri
authors.forename: Ryan A
authors.initials: RA
authors.lastname: McTaggart
authors.forename: Hui
authors.initials: H
authors.lastname: Liao
authors.forename: Joan H F
authors.initials: JH
authors.lastname: Drosopoulos
authors.forename: Virginia L
authors.initials: VL
authors.lastname: Price
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Marcus
authors.forename: Charles R
authors.initials: CR
authors.lastname: Maliszewski
mesh_terms: D000251:Adenosine Triphosphatases / Q000172:deficiency / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D001081:Apyrase / Q000172:deficiency / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D001241:Aspirin / Q000494:pharmacology; D002545:Brain Ischemia / Q000097:blood* / Q000503:physiopathology; D004195:Disease Models, Animal; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010974:Platelet Aggregation / Q000187:drug effects; D020521:Stroke / Q000097:blood / Q000503:physiopathology / Q000517:prevention & control; D013927:Thrombosis / Q000097:blood / Q000503:physiopathology / Q000517:prevention & control
chemical_list: D015703:Antigens, CD; D000251:Adenosine Triphosphatases; D001081:Apyrase; C067869:CD39 antigen; D001241:Aspirin