NADPH Oxidase and Intermittent Hypoxia Figure 8. Oxidative DNA damage was present in the cortex of gp91phox_/Y exposed to IH. 8-OHDG levels in cortex and hippocampus of gp91phox_/Y and C57BL6/J mice exposed to either room air (RA) or intermittent hypoxia for 14 days (IH). (n = 6 per experimental group; *P,0.05). doi:10.1371/journal.pone.0019847.g008 NADPH oxidase subunit protein expression in hypoxia sensitive brain regions involved in learning and memory in rats, and that administration of green tea polyphenols in drinking water attenuated the increase in NADPH oxidase gene expression under IH conditions [94]. In summary, we have shown that excessive NADPH oxidase- mediated superoxide release induced by IH contributes to the cellular damage and consequent behavioral impairments associ- ated with severe forms of OSA. This study suggests that NADPH References 1. 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