H. Yokoyama et al., In vivo EPR imaging by using an acyl-protected hydroxylamine to analyze intracerebral oxidative stress in rats after epileptic seizures, MAGN RES IM, 18(7), 2000, pp. 875-879
EPR imaging by using an acyl-protected hydroxylamine, 1-acetoxy-3-carbamoyl
-2,2,5,5-tetramethypyrrolidine (ACP), in the head of a living rat after kai
nic acid (KA)-induced epileptic seizures was performed. ACP is a stable non
-radical compound, but is easily deprotected with intracellular esterase to
yield a hydroxylamine, which is oxidized by intracellular oxidative stress
to yield an EPR-detectable nitroxide radical. From in vivo image data, the
average values of EPR signal intensity from the hippocampus, striatum, and
cerebral cortex were computed. There was no significant difference in cort
ical signal intensity between the control and KA-treated rats. The signal i
ntensities From the hippocampus and striatum for the KA-treated rats were s
ignificantly higher than those for the control. The in vitro study showed t
hat almost the same quantity of ACP moved into all regions of the brain of
the control and KA-treated rats. These findings indicate that Following a K
A-induced seizure, the oxidative stress in the hippocampus and striatum is
enhanced, but not so in the cerebral cortex. (C) 2000 Elsevier Science Inc.
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