The action of dibutyryl adenosine-3':5'-cyclic monophosphoric acid and theophylline on the isolated cat parotid gland.

In the isolated cat parotid gland intraarterially applied dibutyryl cyclic AMP (db-cAMP) (1.0 mM) produced a slow, but often maintained salivary flow. db-cAMP was also able to potentiate secretion evoked by supramaximal doses of intraarterially applied acetylcholine. Similar secretory effects were obtained also after intraarterial application of theophylline (1.0 mM). The secretory responses due to db-cAMP or theophylline were unaccompanied by measurable acinar membrane potential changes and stayed unchanged after cutting the parasympathetic innervation of the gland and after blocking both cholinergic and beta-adrenergic receptors with atropine (10-minus 7 M), and with D-(minus)-N-isopropyl-p-nitrophenol-ethanolamine (INPEA) (10-minus 5 M), respectively. The possibility of the existence of an acinar adenylate cyclase system functionally linked to the beta-adrenergic membrane receptor is discussed.