Cholecystokinin (CCK) is a gut peptide which induces a syndrome of satiety, including reduced food intake and reduced exploratory behaviors. To investigate the minimal active sequence within the octapeptide molecule for reducing exploratory behavior, all C- and N-terminal fragments of CCK 26-33 (CCK8) were synthesized. Only CCK26-33 [H-Asp-Tyr(SO3H)-Met-Gly-Trp-Met-Asp-Phe-NH2] and CCK27-33 [H-Tyr(SO3H)-Met-Gly-Trp-Met-Asp-Phe-NH2] induced the behavioral effects within a physiological dose range. Smaller fragments as well as unsulfated CCK26-33 and CCK27-33 were inactive in doses as high as 10-3 mol/kg. The requirement of the entire C-terminal heptapeptide for the behavioral effects of CCK is contrasted against the activity of smaller fragments at pancreatic, gastrointestinal and brain CCK receptors.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of Pharmacology and Experimental Therapeutics|
|State||Published - 1984|
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