title: Transient cell depolarization after permanent middle cerebral artery occlusion: an observation by diffusion-weighted MRI and localized 1H-MRS.
abstract: Focal cerebral ischemia causes rapid intensity changes in diffusion-weighted images (DWI) and elevated lactate as detected by localized proton spectroscopy (1H-MRS). To investigate whether such changes can also be evoked by perischemic depolarizations, we combined DWI and 1H-MRS measurements with DC potential recordings. About 40 min after occlusion of the middle cerebral artery in a rat, a negative DC deflection was observed indicating transient cell depolarization. Coincidentally with the depolarization a transient increase of the DWI signal intensity and a partially reversible increase of lactate occurred in the periphery of the ischemic territory. These results show that peri-ischemic depolarization, known to contribute to the evolution of cerebral infarction, evokes disturbances that can be detected by DWI and 1H-MRS.
authors.affiliation: Max-Planck-Institut für neurologische Forschung, Abteilung für experimentelle Neurologie, Köln F. R. Germany.
authors.forename: M L
authors.initials: ML
authors.lastname: Gyngell
authors.forename: T
authors.initials: T
authors.lastname: Back
authors.forename: M
authors.initials: M
authors.lastname: Hoehn-Berlage
authors.forename: K
authors.initials: K
authors.lastname: Kohno
authors.forename: K A
authors.initials: KA
authors.lastname: Hossmann
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D007773:Lactates / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D051381:Rats
chemical_list: D007773:Lactates