title: Establishing a photothrombotic 'ring' stroke model in adult mice with late spontaneous reperfusion: quantitative measurements of cerebral blood flow and cerebral protein synthesis.
abstract: This study sought to establish the photothrombotic 'ring' stroke model with late spontaneous reperfusion in adult mice. By applying a 3.0-mm diameter laser ring-beam (514 nm, 0.21 mm thick, 0.65 W/cm2) onto the exposed skull for 60 secs with concurrent erythrosin B (4.25 mg/kg) intravenous infusion for 15 secs, the centrally located cortical region within the ring locus was progressively encroached by an annular ring-shaped perfusion deficit. In this region, local cerebral blood flow (lCBF) measured by laser-Doppler flowmetry declined promptly after irradiation to 43% of the baseline value at 30 mins poststroke. Using double tracer autoradiography, quantitative lCBF measured with [14C]iodoantipyrine was 46 to 17 to 58 ml/100 g/mins at 4 h to 48 h to 7 days postischemia in this area. Cerebral protein synthesis (CPS), as detected by [3H]leucine incorporation into protein, transiently decreased to 57% to 38% to 112% at 4 h to 48 h to 7 days postischemia in the center region. Morphologically, some neurons in the center region appeared swollen at 4 h. At 48 h, the majority of neurons were severely swollen with eosinophilia and pyknosis, whereas at 7 days poststroke' the tissue morphology became partly restored. The center within the mouse photothrombotic ring lesion thus exhibits reversible alterations of local CBF, CPS and tissue morphology that are reminiscent of the cortical penumbra in other models of focal cerebral ischemia.
authors.affiliation: Umeå Stroke Center, University of Umeå, Umeå, Sweden.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.forename: Weigang
authors.initials: W
authors.lastname: Gu
authors.forename: Konstantin-Alexander
authors.initials: KA
authors.lastname: Hossmann
authors.forename: Günter
authors.initials: G
authors.lastname: Mies
authors.forename: Per
authors.initials: P
authors.lastname: Wester
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects / Q000528:radiation effects; D002244:Carbon / Q000008:administration & dosage / Q000493:pharmacokinetics; D002540:Cerebral Cortex / Q000098:blood supply* / Q000378:metabolism* / Q000473:pathology; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000528:radiation effects; D002561:Cerebrovascular Disorders / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D004923:Erythrosine; D020767:Intracranial Thrombosis / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D007834:Lasers; D008028:Light Coagulation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D014176:Protein Biosynthesis; D015424:Reperfusion; D015203:Reproducibility of Results; D020521:Stroke / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*
chemical_list: D002244:Carbon; D004923:Erythrosine