Effects of a novel NMDA antagonist on experimental stroke rapidly and quantitatively assessed by diffusion-weighted MRI

• Published in: Neurology Vol. 43; no. 2; pp. 397 - 403
• Main Authors: MINEMATSU, K, FISHER, M, LI, L, DAVIS, M. A, KNAPP, A. G, COTTER, R. E, MCBURNEY, R. N, SOTAK, C. H
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 01-02-1993
• Subjects: Animals; Biological and medical sciences; Cerebral Infarction - etiology; Cerebral Infarction - prevention & control; Cerebrovascular Disorders - drug therapy; Cerebrovascular Disorders - pathology; Disease Models, Animal; Guanidines - blood; Guanidines - therapeutic use; Ischemic Attack, Transient - complications; Kinetics; Magnetic Resonance Imaging - methods; Male; Medical sciences; Miscellaneous; Neuropharmacology; Neurotransmitters. Neurotransmission. Receptors; Pharmacology. Drug treatments; Radioligand Assay; Rats; Rats, Sprague-Dawley; Receptors, N-Methyl-D-Aspartate - antagonists & inhibitors; Staining and Labeling; Tetrazolium Salts; Time Factors; Cerebral infarction; Nervous system diseases; Rat; Rodentia; Middle cerebral artery; Cardiovascular disease; Exploration; Neuroprotective agent; Nuclear magnetic resonance imaging; Cerebral disorder; Vascular disease; Vertebrata; Chemotherapy; Experimental disease; Mammalia; Treatment; Animal; Antagonist; Obliteration; NMDA receptor; Cerebrovascular disease
• ISSN: 0028-3878; 1526-632X
• DOI: 10.1212/wnl.43.2.397

We employed diffusion-weighted MRI (DWI) to identify regions of focal brain ischemia during the first 3 hours after permanent occlusion of the middle cerebral artery in rats. Using DWI as early as 30 minutes after the onset of ischemia, it was possible to identify the areas of brain destined to progress to infarction over the next 24 hours in untreated animals, as demonstrated by postmortem evaluation. DWI studies revealed the cerebroprotective effects of a noncompetitive N-methyl-D-aspartate receptor antagonist, CNS 1102, administered 15 minutes postocclusion, both on the cortical and caudoputaminal regions during the initial 3 hours of ischemia. Although the treatment effect lessened over the next 21 hours in a few animals with lower plasma drug levels at 3 hours, postmortem studies demonstrated a 66% reduction in the total volume of infarcted tissue with the treatment and confirmed the DWI results. T2-weighted MRI obtained at similar times revealed little or no abnormality. These results suggest that DWI provides a sensitive in vivo measure of focal cerebral ischemic injury and can assess the beneficial effects of cytoprotective therapy. DWI may be useful in the early evaluation of human stroke patients and in monitoring the effects of cerebroprotective therapies in the clinical setting.