Enables G protein-coupled adenosine receptor activity. Involved in G protein-coupled receptor signaling pathway; regulation of norepinephrine secretion; and regulation of synaptic vesicle exocytosis. Located in presynaptic membrane. Is active in Schaffer collateral - CA1 synapse. Orthologous to human ADORA3 (adenosine A3 receptor). [provided by Alliance of Genome Resources, Apr 2022]