Adenosine A₁ receptors (A₁R) are able to form a heteromeric complex with P2Y₁ receptors (P2Y₁R) that generates A₁R with P2Y₁R-like agonistic pharmacology. A potent P2Y₁R agonist, adenosine 5'-O-(2-thiotriphosphate), binds the A₁R binding pocket of the A₁R/P2Y₁R complex and inhibits adenylyl cyclase activity via G_i/o protein. These mechanisms might be used to fine-tune purinergic inhibition locally at sites where there is a particular oligomerization structure between purinergic receptors and explain the undefined purinergic functions by adenosine and adenine nucleotides.