I highly recommend these books, you will not be disappointed! OMG I LOVE THEM YOU WILL SERIOUSLY NEVER EVER REGRET READING THEM I HAVE BEEN READING THEM FOR 3 YEARS AND I KEEP ON HOPING SOMEONE WILL MAKE MORE OF THE BOXCAR CHILDREN BOOKS READ THEM!!!!!!!!!!
Cholecystokinin is secreted by I-cells in the small intestine and induces contraction of the gall bladder, relaxes the sphincter of Oddi, reduces of gastric acid secretion, increases bile acid production in the liver, delays gastric emptying, and induces digestive enzyme production in the pancreas.
These subunits fire spontaneously in either a tonic or a phasic fashion. Tonic contractions are those contractions that are maintained from several minutes up to hours at a time. These occur in the sphincters of the tract, as well as in the anterior stomach. The other type of contractions, called phasic contractions, consist of brief periods of both relaxation and contraction, occurring in the posterior stomach and the small intestine, and are carried out by the muscularis externa.