title: Magnetic resonance imaging indexes of therapeutic efficacy of recombinant tissue plasminogen activator treatment of rat at 1 and 4 hours after embolic stroke.
abstract: With use of magnetic resonance imaging (MRI), the effects of early and delayed treatment of embolic stroke in rat with recombinant tissue plasminogen activator (rt-PA) were investigated. Rats with embolic stroke were treated with rt-PA at 1 (n = 9) or 4 (n = 7) hours after stroke onset or were untreated (n = 15). Diffusion-weighted imaging, perfusion-weighted imaging, and T2-weighted imaging were performed before and after embolization from 1 hour to 7 days. No significant differences were detected in the relative areas with low cerebral blood flow (CBF), apparent diffusion coefficient of water (ADCw), and T2 between the 4-hour treated group and the untreated group. Significant decreases in the average relative areas with low CBF were detected in the 1-hour treated group from 4 to 48 hours after embolization as compared with the untreated group. The increase in T2 in the 1-hour treated group was significantly lower than in the untreated and 4-hour treated groups. A significant increase in ADCw was detected in the 1-hour treated group at 3 and 24 hours after embolization as compared with the untreated and 4-hour treated groups. Secondary embolization was detected by both MRI and laser scanning confocal microscopy. The data suggest that MRI can detect the efficacy of rt-PA treatment and secondary ischemic damage.
authors.affiliation: Department of Neurology, Henry Ford Health Sciences Center, Detroit, Michigan, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Jiang
authors.forename: R L
authors.initials: RL
authors.lastname: Zhang
authors.forename: Z G
authors.initials: ZG
authors.lastname: Zhang
authors.forename: J R
authors.initials: JR
authors.lastname: Ewing
authors.forename: P
authors.initials: P
authors.lastname: Jiang
authors.forename: G W
authors.initials: GW
authors.lastname: Divine
authors.forename: R A
authors.initials: RA
authors.lastname: Knight
authors.forename: M
authors.initials: M
authors.lastname: Chopp
mesh_terms: D000818:Animals; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D020766:Intracranial Embolism / Q000150:complications* / Q000175:diagnosis / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000627:therapeutic use; D020521:Stroke / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology* / Q000473:pathology; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*
chemical_list: D005343:Fibrinolytic Agents; D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator