Assessment of neuroprotective ability of a spin trap, alpha-phenyl-N-tert-butylnitrone, against malonate-induced ischemic injury of rat brain by apparent water diffusion coefficient mapping.

Ischemic brain injury induced by injection of 3-micromol malonate into the left striatum of male Sprague-Dawley rats was examined by apparent water diffusion coefficient (ADC) mapping of magnetic resonance imaging. The region surrounding the injection core was imaged as a hypointense area in ADC mapping and ADC values in the regions were significantly decreased 3 and 6 h after ischemia. Significant reduction of the hypointense area and the recovery of ADC values were observed in rats to which alpha-phenyl-N-tert-butylnitrone (PBN) was intraperitoneally administered 1 h before ischemia. Since ADC mapping has been reported to be a suitable method for evaluating the extent and the degree of cytotoxic edema in the early period after the onset of ischemia, the present results prove that PBN is able to prevent early ischemic insults such as cytotoxic edema.