Background:

8-Aminoadenine is an agonist of adenine receptor with Ki value of 0.0341 μM [1].

Adenine receptor is a G protein-coupled receptor activated by the nucleoside adenosine. There are four types of adenosine receptors: A1, A2A, A2B and A3. A1 and A2A receptors play an important role in the heart, regulating coronary blood flow and myocardial oxygen consumption. A2B and A3 receptors are involved in inflammation and immune responses.

8-Aminoadenine is an adenine receptor agonist with Ki values of 0.0341 and 6.51 μM for human and rat, respectively. In HEK293 cell membrane, 8-Aminoadenine was more potent than adenine (Ki = 0.0471 μM) and exhibited 190-fold more potent than the rat binding site. In 1321N1 astrocytoma cells expressing the rAde1R, 8-Aminoadenine (500 μM) inhibited isoproterenol-stimulated cAMP accumulation, which suggested that 8-Aminoadenine inhibited adenine uptake [1].

Reference:
[1].  Borrmann T, Abdelrahman A, Volpini R, et al. Structure-activity relationships of adenine and deazaadenine derivatives as ligands for adenine receptors, a new purinergic receptor family. J Med Chem, 2009, 52(19): 5974-5989.