title: Rate and extent of leakage of a magnetic resonance contrast agent tend to be lower under isoflurane anesthesia in comparison to halothane in a rat model of embolic stroke.
abstract: Cerebral blood flow (CBF) and blood-brain barrier (BBB) permeability by arterial spin labeling (ASL)- and dynamic contrast enhanced (DCE)-magnetic resonance imaging (MRI), respectively were repeatedly measured under either halothane (N  =  5) or isoflurane (N  =  5) anesthesia in a rat stroke model of embolic occlusion of middle cerebral artery (MCA). Cerebral blood flow measurements were made after MCA embolization, following intravenous recombinant tissue plasminogen activator (rtPA) treatment at 3 hours post-ictus and again at 48 hours. Blood-brain barrier opening was examined after rtPA infusion and again at 48 hours. Data were analyzed using paired t-tests and significance considered at P < 0·05. The extent and magnitude of CBF reduction due to stroke did not differ between the two groups. Blood-to-brain forward rate constant, K(trans), a measure of BBB permeability, for an MRI contrast agent gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA), was elevated in the ipsilateral hemisphere in both cohorts. However, isoflurane-anesthetized rats exhibited a trend of lower K(trans) values at 48 hours (P  =  0·06) indicating reduced BBB damage in the ipsilateral hemisphere. The area of BBB opening followed a similar trend with the isoflurane-anesthetized group exhibiting a smaller area of BBB damage acutely and at 48 hours compared to the halothane-anesthetized group.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Bezerra
authors.forename: Morris
authors.initials: M
authors.lastname: Brown
authors.forename: William
authors.initials: W
authors.lastname: Alarcon
authors.forename: Kishor
authors.initials: K
authors.lastname: Karki
authors.forename: Robert A
authors.initials: RA
authors.lastname: Knight
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Keenan
authors.forename: Tavarekere N
authors.initials: TN
authors.lastname: Nagaraja
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects / Q000503:physiopathology; D002545:Brain Ischemia / Q000473:pathology / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology; D003287:Contrast Media; D004195:Disease Models, Animal; D019786:Gadolinium DTPA; D006221:Halothane / Q000494:pharmacology*; D020244:Infarction, Middle Cerebral Artery; D020766:Intracranial Embolism / Q000473:pathology / Q000503:physiopathology; D007530:Isoflurane / Q000494:pharmacology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D017208:Rats, Wistar; D020521:Stroke / Q000473:pathology / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D018685:Anesthetics, Inhalation; D003287:Contrast Media; D007530:Isoflurane; D019786:Gadolinium DTPA; D006221:Halothane
keywords: ASL-MRI,; Blood–brain barrier,; DCE-MRI,; Inhalational anesthetics,; Ktrans,; Middle cerebral artery