Adenosine regulation of cyclic AMP in corneal endothelium

Adenosine receptor agonists increased cyclic AMP in cultures of bovine corneal endothelium up to 12-fold over control. Effects were dose-dependent between 1 microM and 0.5 mM adenosine. N6-methyladenosine produced a greater maximal effect but was approximately 10-fold less potent. Isoproterenol and N6-methyladenosine produced an additive response. Propranolol blocked the isoproterenol, but not the adenosine effect on cyclic AMP. Adenine-9-beta-D-arabinofuranoside had no effect on cyclic AMP alone, but inhibited stimulations by N6-methyladenosine, isoproterenol and forskolin. These data indicate the presence of specific adenosine receptors which stimulate adenylate cyclase in cultured bovine corneal endothelium.