title: Galanin inhibits cholecystokinin secretion in STC-1 cells.
abstract: Neuropeptides such as gastrin releasing peptide and pituitary adenylate cyclase activating polypeptide (PACAP) stimulate CCK secretion from CCK producing cells. We hypothesized that in addition to somatostatin, galanin may also play an inhibitory role on CCK secretion. The effect of galanin on CCK secretion was studied in a CCK-producing murine neuroendocrine tumor cell line, STC-1. Galanin below 10 nM did not affect basal CCK secretion but dose- and time-dependently inhibited KCl-stimulated CCK secretion. Galanin also inhibited forskolin-, bombesin- and PACAP- but not dibutyryl cAMP- or beta-TPA-stimulated CCK secretion. The inhibitory effect of galanin was reduced partially by a blocker of ATP-sensitive K+ channel (K+ ATP), glibenclamide, and prevented by pretreatment of the cells with PTX. The results indicated galanin regulates CCK secretion by modulation of K+ ATP and cAMP production through receptors coupled to a PTX-sensitive G protein.
mesh_terms: D037361:Adenylate Cyclase Toxin; D000818:Animals; D001839:Bombesin / Q000494:pharmacology; D002460:Cell Line; D002766:Cholecystokinin / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D019004:Galanin / Q000494:pharmacology*; D005905:Glyburide / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D018358:Neuroendocrine Tumors; D009479:Neuropeptides / Q000494:pharmacology; D018377:Neurotransmitter Agents / Q000494:pharmacology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D026902:Potassium Channel Blockers; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D014407:Tumor Cells, Cultured; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: C495402:Adcyap1 protein, mouse; C495403:Adcyap1 protein, rat; D037361:Adenylate Cyclase Toxin; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D026902:Potassium Channel Blockers; D010566:Virulence Factors, Bordetella; D005576:Colforsin; D011189:Potassium Chloride; D019004:Galanin; D002766:Cholecystokinin; D000242:Cyclic AMP; D001839:Bombesin; D005905:Glyburide