Changes in apparent diffusion coefficients of metabolites in rat brain after middle cerebral artery occlusion measured by proton magnetic resonance spectroscopy.
Diffusion-weighted proton MR spectroscopy and imaging have been applied to a rat brain model of unilateral middle cerebral artery occlusion between 1 and 4 hr post occlusion. Similar apparent diffusion coefficients (ADC) of most metabolites were observed within each hemisphere. In the ischemic ipsilateral hemisphere, the ADCs were (0.083--0.116). 10(-3) mm(2)/sec for lactate (Lac), alanine (Ala), gamma-amino butyric acid (GABA), N-acetyl aspartate (NAA), glutamine (Gln), glutamate (Glu), total creatine (tCr), choline-containing compounds (Cho), and myo-inositol (Ins), in the contralateral hemisphere (0.138--0.158). 10(-3) mm(2)/sec for NAA, Glu, tCr, Cho, and Ins. Higher ADCs was determined for taurine (Tau) in the ipsilateral (0.144. 10(-3) mm(2)/sec) and contralateral (0.198. 10(-3) mm(2)/sec) hemisphere. In the ischemic hemisphere, a relative ADC decrease to 65--75% was observed for NAA, Glu, tCr, Cho, Ins and Tau, which was similar to the decrease of the water ADC (to 67%). The results suggest a common cause of the observed ADC changes and provide a broader experimental basis to evaluate theories of water and metabolite diffusion. Magn Reson Med 45:383-389, 2001.
Dreher
W
W
Universität Bremen, Biologie/Chemie, Bremen, Germany. dreher@tomo.uni-bremen.de
Busch
E
E
Leibfritz
D
D
D000818:Animals; D004058:Diffusion; D004292:Dominance, Cerebral / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology*; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051381:Rats; D017208:Rats, Wistar