Acute postischemic renormalization of the apparent diffusion coefficient of water is not associated with reversal of astrocytic swelling and neuronal shrinkage in rats
Department of Neurology; Graduate School of Biomedical Sciences
Animals; Astrocytes; Brain; Brain Ischemia; Diffusion; Magnetic Resonance Imaging; Male; Microscopy, Electron; Neurons; Rats; Rats, Sprague-Dawley; *Reperfusion; Reperfusion Injury; Time Factors; Water
Neurology | Neuroscience and Neurobiology
BACKGROUND AND PURPOSE: Initially decreased apparent diffusion coefficient (ADC) values are reversible if reperfusion is rapidly performed after focal brain ischemia. We sought to determine if reperfusion-induced renormalization of initially abnormal values indicates reversal of cellular, morphologic changes that occur during acute ischemia. METHODS: Eighteen rats underwent 30 minutes of middle cerebral artery occlusion (MCAO) without reperfusion (group A, n = 6), with 1.5 hours of reperfusion (group B, n = 6), or with 12 hours of reperfusion (group C, n = 6). Diffusion- and perfusion-weighted MR images were obtained at the end of MCAO and 1.5 and 12 hours after reperfusion. Immediately after the final MR study, the brains were fixed by cardiac perfusion with 4% paraformaldehyde. Neuronal injury was evaluated on hematoxylin-eosin-stained slices, and astrocytic size was determined by the area of glial fibrillary acidic protein (GFAP) plus S-100 expression. RESULTS: In group A in which ADC values decreased significantly, 47 +/-12% of the neurons were slightly shrunken; astrocytes were moderately swollen, and the area expressing GFAP plus S-100 was larger than that in the contralateral hemisphere (117 microm(2) +/- 6 vs 89 microm(2) +/- 2; P
AJNR Am J Neuroradiol. 2002 Feb;23(2):180-8.
AJNR. American journal of neuroradiology
Li, Fuhai; Liu, Kai-Feng; Silva, Matthew D.; Meng, Xiangjun; Gerriets, Tibo; Helmer, Karl G.; Fenstermacher, Joseph D.; Sotak, Christopher H.; and Fisher, Marc, "Acute postischemic renormalization of the apparent diffusion coefficient of water is not associated with reversal of astrocytic swelling and neuronal shrinkage in rats" (2002). Open Access Articles. 5.