Sleep regulation adenosine

In addition, adenosine is implicated in sleep regulation. During periods of extended wakefulness, extracellular adenosine levels rise as a result of metabolic activity in the brain, and this increase promotes sleepiness. During sleep, adenosine levels fall. Caffeine promotes wakefulness by blocking the interaction of extracellular adenosine with its neuronal receptors. ... 

One of the distinctive features of TMN neurons is that they contain high levels of adenosine deaminase, a key enzyme involved in deamination of adenosine, a mediator of homeostatic sleep regulation (Thakkar et al, 2003a, b). 

Urade, Y., el al. (2003). Sleep regulation in adenosine A2A receptor-deficient mice. Neurology 61, S946. 

Methippara, M. M., Kumar, S., Alam, Md. N., Szymusiak, R., 8r McGinty, D. (2005). Effects on sleep of microdialysis of adenosine A1 and A2A receptor analogs into the lateral preoptic area of rats. Am. J. Physiol. Regul. Integr. Comp. Physiol. 289, 1715-23. 

Figure 13.2 Schematic representation of the molecular mechanisms of sleep wake regulation by PGD2, PGE2, adenosine, histamine, and orexin.

Basheer, R., et al. (2004). Adenosine and sleep-wake regulation. Prog. Neurobiol. 73, 79-96. 

Stenberg D, Litonius E, Halldner L, Johansson B, Fredholm B, Porkka-Heiskanen T. Sleep and its homeostatic regulation in adenosine Al-receptor knockout mice. Soc Neurosci Abst 2002 474.7. 

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