Tissue factor contributes to microvascular defects after focal cerebral ischemia.
Stroke
; 24(6): 847-53; discussion 847, 1993 Jun.
Article
em En
| MEDLINE
| ID: mdl-8506556
ABSTRACT
BACKGROUND AND PURPOSE:
Microvascular perfusion defects occur after occlusion and reperfusion of the middle cerebral artery in examples of focal cerebral ischemia. In addition to cellular (eg, polymorphonuclear leukocyte) contributors to the focal "no-reflow" phenomenon, activation of coagulation may also play a role. We have tested a potential role of tissue factor-mediated coagulation in the microvascular perfusion defects seen after focal cerebral ischemia-reperfusion in a baboon model of reversible middle cerebral artery occlusion with the murine anti-tissue factor monoclonal antibody TF9-6B4. Tissue factor is the principal resident procoagulant substance in cerebral tissues and has a distinct perivascular distribution.METHODS:
Microvascular patency in the basal ganglia after 3-hour middle cerebral artery occlusion and 1-hour reperfusion was quantified by computerized video imaging of carbon-tracer perfused tissues. Animals were randomized to receive intravenous TF9-6B4 (10 mg/kg) 10 minutes before middle cerebral artery occlusion (n = 6) or no treatment (n = 6) in an open study.RESULTS:
In the control animals, a significant decrease in patency was confirmed in microvessels less than 30 microns in diameter. Infusion of TF9-6B4 before middle cerebral artery occlusion produced a stable maximal level of circulating antibody within 10 minutes, which lasted the duration of ischemia and reperfusion. An increase in reflow in microvessels of all size classes occurred after TF9-6B4 infusion, which was significant in those 7.5 to 30 microns (P = .038) and 30 to 50 microns (P = .013) in diameter.CONCLUSIONS:
These results indicate that tissue factor-mediated events may also contribute to no-reflow in noncapillary microvessels after focal cerebral ischemia.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Transtornos da Coagulação Sanguínea
/
Tromboplastina
/
Isquemia Encefálica
/
Microcirculação
Tipo de estudo:
Etiology_studies
/
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Stroke
Ano de publicação:
1993
Tipo de documento:
Article