Additive wake-promoting actions of medial basal forebrain noradrenergic or α1- and β-receptor stimulation

Abstract

The locus coeruleus-noradrenergic system exerts an activating influence on forebrain neuronal and behavioral activity states, in part through the actions of noradrenergic β-receptors in the medial septal (MS) and medial preoptic (MPOA) areas. MPOA α1-receptors exert similar wake-promoting actions. The current study examines the influence of α1-receptors located within MS on sleep-wake state. In addition, the extent to which α1 and β-receptors located within MS and MPOA interact in the modulation of behavioral state was investigated by examining the effects of individual or combined infusion of α1- and β-agonists into these regions. Results show that α1-receptors located within MS exert wake-promoting actions. Within both MS and MPOA, additive wake-promoting actions were observed with α1 and β-receptor stimulation, the sum of which contributes to the overall arousal state of the animal.