腺苷和睡眠觉醒调节

腺苷作为神经调质,调节多种神经生物学功能.随觉醒时间延长,动物脑内腺苷水平逐渐增高,在睡眠期显著降低.因此,腺苷被认为是调节睡眠的内稳态因子之一.腺苷受体(receptor,R)有A1R、A2AR、A2BR和A3R四种亚型,其中A1R和A2AR与诱导睡眠相关.激活A1R可抑制促觉醒神经元诱导睡眠,也可抑制促眠神经元导致...

Adenosine and Sleep-Wake Regulation

Adenosine may function as a neuromodulator in the central nervous system. The extracellular concentration of adenosine increases in the brain during prolonged wakefulness and decreases during the sleep recovery period. Therefore, adenosine is proposed to act as one of homeostatic regulators of sleep. There are four adenosine receptor subtypes, adenosine A1 receptor (A₁R), A_2AR, A_2BR and A₃R. Both the adenosine A₁R and A_2AR are demonstrated to be involved in sleep induction. Inhibition of wake-promoting neurons via the A₁R mediates the sleep-inducing effects of adenosine, whereas activation of A₁R in sleep-promoting neurons induces wakefulness, suggesting that A₁R regulates the sleep-wake cycle in a site-dependent manner. On the other hand, the A_2AR mediates the somnogenic effects of endogenous PGD₂. A_2AR agonist induces the most potent sleep similar to physiological sleep among somnogens reported so far, whereas blockade of A_2AR induces wakefulness. Among adenosine receptors responsible for sleep induction, the role of A_2AR is predominant. This paper presents an overview of the current knowledge about the role of adenosine in the sleep-wake regulation and briefly discusses the potential therapeutic applications of agonists and antagonists of these receptors in sleep disorders.