Inducible nitric oxide synthase and AMP-activated protein kinase in basal forebrain during prolonged waking.

Activation of inducible nitric oxide synthase (iNOS) and the subsequent production of adenosine in basal forebrain in the early phase of prolonged waking suggest that the wake-promoting basal forebrain is selectively sensitive to the metabolic demands of waking. In this study, iNOS protein, and activation of AMP-activated protein kinase - a marker of decreased cellular energy charge - were measured in the rat basal forebrain and cortex during prolonged waking (1.5-, 3- and 6 h). The site-specific increase in iNOS protein was accompanied with AMP-activated protein kinase activation in the basal forebrain. In contrast, no changes were found in the cortex. These results further support the hypothesis that basal forebrain, as compared to cortex, is selectively sensitive to the effects of prolonged waking.