Vasoactive intestinal peptide stimulates cyclic AMP metabolism in choroid plexus epithelial cells

Some peptides of the glucagon-secretin family were found to stimulate intracellular cyclic AMP accumulation in cultured bovine choroid plexus epithelial cells. Vasointestinal peptide and porcine intestinal peptide at concentrations of 30 and 300 nM, respectively, evoked 50-fold elevations of cyclic AMP; half-maximal responses were obtained with concentrations of 15 and 102 nM for the two peptides, respectively. Secretin and glucagon each produced 25- to 50-fold elevations of cyclic AMP at 330 microM, but showed no effect below 3 microM. Gastric inhibitory peptide and prealbumin had little or no response at any concentration tested. Experiments measuring the cellular cyclic AMP accumulation in response to pairs of peptides suggested that vasointestinal peptide, porcine intestinal peptide and secretin act through a common receptor. Studies with antagonists to isoproterenol and histamine indicated that this receptor is distinct from the beta-adrenergic and H2-histamine receptors known to exist on choroidal cells.