chyme(redirected from chymus)
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chyme(kīm), semiliquid substance found in the stomach and resulting from the partial digestion of food by the salivary enzyme amylase, the gastric enzyme pepsin, and hydrochloric acid. Secretion of hydrochloric acid by the stomach makes the chyme strongly acidic. The rhythmic muscular action of the stomach wall (peristalsis) moves the chyme into the duodenum, the first section of the small intestine, where it stimulates the release of secretin, a hormone that increases the flow of pancreatic juice as well as bile and intestinal juices. Chyme also stimulates the release of cholecystokinin, a hormone that primarily increases the flow of bile but also increases the proportion of digestive enzymes in the pancreatic juice.
the fluid or semifluid contents of the small intestine in animals and man, consisting of gastric digestive products mixed with bile, the secretions of the pancreas and intestinal glands, desquamated epithelium, and microorganisms. Chyme also contains enzymes of the pancreatic juice, such as proteases, α-amylase, and lipase, as well as intestinal enzymes, such as enterokinase, carbohydrases, peptidases, monoglyceride lipase, and phosphatase. Its composition depends on the food ingested and the secretory activity of the digestive system.
In man, about 400 g of chyme per day pass from the small intestine to the large intestine. The motor activity of the intestine agitates the chyme, thus promoting better digestion and absorption of food substances. Specially prepared chyme has therapeutic properties: it is used in certain digestive disorders and metabolic disturbances in agricultural animals.
REFERENCEFiziologiia pishchevareniia. Leningrad, 1974. (Rukovodstvo pofisiologii.)
N. M. TIMOFEEVA