The interaction between adenosine and PGE2 receptors linked to adenylate cyclase was investigated in cultured endothelial cells derived from dissociated cerebral microvessels. PGE2 stimulated adenylate cyclase in dose dependent manner (1nm-100 mu M) while adenosine increased the activity of adenylate cyclase only at high concentration of the drug (0.01- 0.1mM). Increasing concentration of adenosine with PGE2 (10- 6M) had a statistically significant effect on adenylate cyclase stimulation only at lower doses of adenosine (1-10nM). The same concentrations of adenosine (1-10nM) alone did not enhance significantly the formation of cAMP. Those results indicate that both vasoactive substances adenosine and PGE2 have an effect on receptors linked to adenylate cyclase.
