CCK stimulates secretion of ______ juice that is rich in
digestive enzymes. It also causes contraction of the wall of the
gallbladder, which squeezes stored bile out of the gallbladder into
the cystic duct and through the common bile duct.
• In addition, CCK causes relaxation of the sphincter of the ______ (sphincter of Oddi), which
allows pancreatic juice and bile to flow into the duodenum.
• CCK also slows ______ by
promoting contraction of the pyloric sphincter, produces satiety (a
feeling of fullness) by acting on the hypothalamus in the brain,
promotes normal growth and maintenance of the pancreas, and
enhances the effects of secretin.
• Acidic chyme entering the duodenum stimulates the release of ______ from the S cells of the small
intestinal crypts of Lieberkühn.
• In turn, secretin stimulates the flow of ______ that is rich in bicarbonate
(HCO3) ions to buffer the acidic chyme that enters the duodenum
from the small intestine.
• Besides this major effect, secretin inhibits secretion of ______, promotes normal growth
and maintenance of the pancreas, and enhances the effects of CCK.
• Overall, secretin causes buffering of acid in chyme that reaches the
duodenum and slows production of acid in the stomach.
