Elsevier

Brain Research

Volume 944, Issues 1–2, 19 July 2002, Pages 190-194
Brain Research

Short communication
Orexin neurons of the hypothalamus express adenosine A1 receptors

https://doi.org/10.1016/S0006-8993(02)02873-1Get rights and content

Abstract

Adenosine is a putative sleep factor with effects mainly mediated by the A1 receptor. Recent studies have implicated the hypothalamic orexin/hypocretin-containing neurons in the control of sleep–wakefulness. To help determine if adenosine might play a role in the control of orexin neurons, immunohistochemistry was used to characterize the distribution of adenosine A1 receptor protein on the orexinergic neurons. About 30% of orexin-containing neurons were labeled. The data supports the presence of adenosine A1 receptors on orexinergic neurons and suggests a possible substrate for a functional role of adenosine in the regulation of orexinergic activity.

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Acknowledgements

The Department of Veterans Affairs Medical Research Services (RWM), the National Institute of Mental Health Grants R37MH39683 (RWM) and KO1MH01798 (MMT) and the Sleep Medicine Education and Research Foundation (MMT) supported this work. We thank John Franco of the VAMC Animal Research Facility for providing care for the animals.

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