The adenosine receptor (A2A/A2B receptor)
There are at least four subtypes of the adenosine receptor ¾ A1, A2A, A2B and A3 receptors. Adenosine receptors are all coupled to G-proteins and the A2A and A2B subtypes are associated with stimulatory G-proteins. Activation of the A2A and A2B receptors causes activation of adenylate cyclase and phospholipase C, resulting in the stimulation of neurotransmission. A2A receptors are co-expressed in the brain with dopamine D2 receptors, especially in the striatum, olfactory tubercle and nucleus accumbens. Low levels of A2 receptors have been reported in the brains of rats.
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References
Adenosine receptor A2A. Affinity bioreagents. http://www.bioreagents.com/index.cfm/fuseaction/products.detail/Product/PA1-042 Accessed on 7 May 2002.
The pharmacology and biochemistry of adenosine receptors. The University of Nottingham. http://www.nottingham.ac.uk/~mqzwww/adenosine.html Accessed on 7 May 2002
Pharmacol Rev. 1998 Sep;50(3):413-492