Frontiers in Bioscience-Landmark (FBL) is published by IMR Press from Volume 26 Issue 5 (2021). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on imrpress.com as a courtesy and upon agreement with Frontiers in Bioscience.
Is there a major role for adenosine a2a receptors in anxiety?
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Academic Editor: John Salamone
Clinical investigations, pharmacological studies and models of genetically modified rodents have implicated adenosine in the etiology and modulation of different types of anxiety. Caffeine, a non selective adenosine antagonist, has been involved in many of them. Adenosine seems to interact with other neurotransmitter systems and with some substances like alcohol, which elevate the basal levels of adenosine. A growing body of data describes the role of adenosine A1 and A2A receptors on anxiety. However, a differential role of adenosine receptors is not very clear. A1 receptor antagonists seem to be anxiogenic, but the absence of any effect of some of them and the opposite effects of others does not strongly support this conclusion. Human studies suggest that there is a susceptibility locus for panic disorder and agoraphobia within the receptor A2A gene. On the other hand, pharmacological data do not advocate for a clear implication of the A2A receptor. More research in this area is needed.