Interaction of 2-phenylaminoadenosine (CV 1808) with adenosine systems in rat tissues.

2-Chloroadenosine (2-CADO) and 2-phenylaminoadenosine (CV 1808) were compared in a CNS purinergic receptor binding assay and the inhibition of neurogenic contractions of the vas deferens. Both 2-CADO and CV 1808 are more potent than adenosine in both preparations. CV 1808 was 10 times more active than dipyridamole in enhancing the response of the vas deferens to exogenous adenosine. Thus, CV 1808 may owe its potent coronary vasodilator activity to both a direct action on adenosine receptors and the ability to augment adenosine responses.