Extracellular levels of the sleep homeostasis mediator, adenosine, are regulated by glutamatergic neurons during wakefulness and sleep

摘要

The basal forebrain (BF) is recognized as one of the crucial brain regions that regulate sleep and wakefulness and an increase in the extracellular concentration of adenosine in the BF during wakefulness and associated stimulation of A1 receptors are known to increase the pressure to sleep. How different neuronal populations control adenosine release is, however, unclear. Blanco-Centurion et al. [1] investigated the role of cholinergic neurons in the BF by administering 192–IgG– saporin to lesion them, but surprisingly the results indicated that adenosine from cholinergic neurons in BF are not essential to sleep induction. Then, Xu et al. [2] showed that BF glutamatergic activity had a stronger arousal effect than cholinergic neurons. However, how to measure the concentration of adenosine in the BF dynamically, especially during REM sleep, is a big challenge.