title: Distinct spatiotemporal patterns of spreading depolarizations during early infarct evolution: evidence from real-time imaging.
abstract: Experimental and clinical studies indicate that waves of cortical spreading depolarization (CSD) appearing in the ischemic penumbra contribute to secondary lesion growth. We used an embolic stroke model that enabled us to investigate inverse coupling of blood flow by laser speckle imaging (CBF(LSF)) to CSD as a contributing factor to lesion growth already in the early phase after arterial occlusion. Embolization by macrospheres injected into the left carotid artery of anesthetized rats reduced CBF(LSF) in the territories of the middle cerebral artery (MCA) (8/14 animals), the posterior cerebral artery (PCA) (2/14) or in less clearly defined regions (4/14). Analysis of MCA occlusions (MCAOs) revealed a first CSD wave starting off during ischemic decline at the emerging core region, propagating concentrically over large portions of left cortex. Subsequent recurrent waves of CSD did not propagate concentrically but preferentially circled around the ischemic core. In the vicinity of the core region, CSDs were coupled to waves of predominantly vasoconstrictive CBF(LSF) responses, resulting in further decline of CBF in the entire inner penumbra and in expansion of the ischemic core. We conclude that CSDs and corresponding CBF responses follow a defined spatiotemporal order, and contribute to early evolution of ischemic territories.
authors.affiliation: Max Planck Institute for Neurological Research, Cologne, Germany.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kumagai
authors.forename: Maureen
authors.initials: M
authors.lastname: Walberer
authors.forename: Hajime
authors.initials: H
authors.lastname: Nakamura
authors.forename: Heike
authors.initials: H
authors.lastname: Endepols
authors.forename: Michael
authors.initials: M
authors.lastname: Sué
authors.forename: Stefan
authors.initials: S
authors.lastname: Vollmar
authors.forename: Sasan
authors.initials: S
authors.lastname: Adib
authors.forename: Günter
authors.initials: G
authors.lastname: Mies
authors.forename: Toshiki
authors.initials: T
authors.lastname: Yoshimine
authors.forename: Michael
authors.initials: M
authors.lastname: Schroeter
authors.forename: Rudolf
authors.initials: R
authors.lastname: Graf
mesh_terms: D000465:Algorithms; D000818:Animals; D002545:Brain Ischemia / Q000473:pathology; D002544:Cerebral Infarction / Q000473:pathology*; D003199:Computer Systems; D013181:Cortical Spreading Depression / Q000502:physiology*; D003627:Data Interpretation, Statistical; D018450:Disease Progression; D017078:Laser-Doppler Flowmetry; D007834:Lasers; D008297:Male; D008863:Microspheres; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D012212:Rheology