In situ visualization of O2- and O2--derived oxidant production was assessed by hydroethidine histochemistry [32,33]. Mice were injected with dihydroethidium (10 mg/kg, i.p.) in 0.5% carboxymethyl cellulose 2.5 hours after poly I:C. injection. Brains were harvested 30 minutes later and frozen sections (15 μm) were examined for hydroethidine oxidation product, ethidium accumulation, by fluorescence microscopy (excitation 510 nm; emission 580 nm).
