Adenosine important is Sleep
Research data suggests that adenosine is indeed an important endogenous, homeostatic sleep factor and it is likely to be mediating the sleepiness that follows prolonged wakefulness because it acts as a direct negative feed-back inhibitor of neuronal activity. Adenosine is proposed to act as a homeostatic regulator of sleep and to be a link between the humoral and neural mechanisms of sleep-wake regulation. Both the adenosine A(1) receptor (A(1)R) and A(2A)R are involved in sleep induction.