title: Visualization by mass spectrometry of 2-dimensional changes in rat brain lipids, including N-acylphosphatidylethanolamines, during neonatal brain ischemia.
abstract: Spatial synthesis of N-acyl-phosphatidylethanolamines (NAPEs) and N-acylethanolamines (NAEs) during ischemia-reperfusion in neonatal rats has been investigated and compared to the spatial degradation of other phospholipids. Ischemia was induced in anesthetized Wistar P7 rat pups by left middle cerebral artery electrocoagulation combined with a transient and concomitant occlusion of both common carotid arteries. Pups were sacrificed after 24 and 48 h. Sham-treated animals were sacrificed after 48 h. The frozen brains were sliced and subjected to desorption electrospray ionization imaging mass spectrometry. There was a remarkable increase in the levels of many species of NAPEs in the whole injured area at both time points, and a clear but minor increase in selected NAEs. In the ischemic area, the sodium adducts of phosphatidylcholine and of lyso-phosphatidylcholine accumulated and the potassium adduct of phosphatidylcholine disappeared, indicating breakdown of the Na(+)/K(+) pump. Free fatty acids, e.g., arachidonic and docosahexaenoic acids, tended to be more abundant in the periphery than in the center of the ischemic area and showed different spatial distribution. NAPEs are synthesized in the whole ischemic area where the cells seem to be dead and other phospholipids are degraded. Free fatty acids can be found in the periphery of the ischemic area.
authors.affiliation: Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Janfelt
authors.forename: Niels
authors.initials: N
authors.lastname: Wellner
authors.forename: Pierre-Louis
authors.initials: PL
authors.lastname: Leger
authors.forename: Julia
authors.initials: J
authors.lastname: Kokesch-Himmelreich
authors.forename: Steen Honoré
authors.initials: SH
authors.lastname: Hansen
authors.forename: Christiane
authors.initials: C
authors.lastname: Charriaut-Marlangue
authors.forename: Harald Severin
authors.initials: HS
authors.lastname: Hansen
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001923:Brain Chemistry; D002545:Brain Ischemia / Q000378:metabolism*; D004983:Ethanolamines / Q000032:analysis; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005260:Female; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism; D008055:Lipids / Q000032:analysis*; D008297:Male; D010714:Phosphatidylethanolamines / Q000032:analysis* / Q000378:metabolism; D010955:Plasmalogens / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D004983:Ethanolamines; D005230:Fatty Acids, Nonesterified; D008055:Lipids; C022203:N-acylethanolamines; D010714:Phosphatidylethanolamines; D010955:Plasmalogens