Abstract
In the vascularly isolated and self -hemoperfused dog pancreas, secretin (0.025 clinical units) and adenosine (1.0 mg) administered intra-arterially (i.a.) increased tissue cyclic AMP level by about 46% and 37%, respectively. Although the increases in the nucleotide were not statistically different, only secretin stimulated exocrine secretion. The increase in cyclic AMP induced by adenosine was significantly reversed by pretreatment with theophylline (0.3 mg, i.a.). These results suggest that the effect of adenosine on cyclic AMP formation occurs mainly in the non-exocrine system of the dog pancreas through A2/Ra-receptors.
