Effect of somatostatin and dopaminergic agents on bovine pituitary phosphodiesterase activity

The effects of somatostatin and dopaminergic agents on pituitary cyclic nucleotide phosphodiesterases that had been partially purified through DEAE cellulose column chromatography were studied. Somatostatin, L-dopa, dopamine and CB-154(2-bromo-alpha-ergocriptine) competitively inhibited the pituitary cyclic AMP phosphodiesterase activity, especially that of the low Km enzyme. This inhibition was most potent in the case of somatostatin and CB-154.