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bile,bitter alkaline fluid of a yellow, brown, or green color, secreted, in man, by the liver. Bile, or gall, is composed of water, bile acids and their salts, bile pigments, cholesterol, fatty acids, and inorganic salts. In man it is stored in the gall bladdergall bladder,
small pear-shaped sac that stores and concentrates bile. It is connected to the liver (which produces the bile) by the hepatic duct. When food containing fat reaches the small intestine, the hormone cholecystokinin is produced by cells in the intestinal wall and
..... Click the link for more information. and, in response to the action of the hormone cholecystokinen (whose secretion by the intestine is stimulated by the presence of food), is secreted via the cystic and common ducts into the duodenum. The bile salts aid in digestion by emulsifying fats, enabling the absorption of fats and of the fat-soluble vitamins (A, D, E, and K) through the intestinal wall. Since unabsorbed fats tend to coat other foods and prevent the action of digestive enzymes, adequate fat absorption mediated by bile salts is necessary for the complete digestion of food and the prevention of decomposition of partially digested foods by intestinal bacteria. The alkaline bile acts to neutralize the stomach acid in the small intestine, providing a more optimum environment for the pancreatic enzymes. The bile is a route of excretion for many drugs and metabolites; cholesterol is excreted almost entirely in the bile, as are breakdown products of heme, such as bilirubin, which color the bile and are known as the bile pigments. If the flow of bile is impeded by inflammation, gall stones, or other abnormality, digestive disturbances and frequently jaundicejaundice
, abnormal condition in which the body fluids and tissues, particularly the skin and eyes, take on a yellowish color as a result of an excess of bilirubin. During the normal breakdown of old erythrocytes (red blood cells), their hemoglobin is converted into bilirubin.
..... Click the link for more information. result.
a continuously manufactured secretion of the adenoblasts of the liver in vertebrates and man.
The liver of the human adult secretes as much as 1.2 liters of bile in 24 hours; in some diseases bile secretion may increase or decrease. There is a distinction between hepatic bile, a slightly viscous golden-yellow fluid secreted directly into the intestine independent of digestion, and cystic bile, which accumulates in the gallbladder (a viscous, yellow-brown or greenish fluid) and is discharged into the intestine according to the amount of food present there. The principal components of bile are water, bile acids, bile pigments, cholesterol, and inorganic salts. Of the enzymes, phosphatases have been found in the bile; of the hormones, thyroxine (the hormone of the thyroid gland), whose discharge from the body occurs to a significant degree with the bile, has been found. In the intestine, bile promotes the decomposition, saponification, emulsification, and absorption of fats, and it intensifies peristalsis. The discharge of bile into the intestine is regulated by the entry of food into the intestine and by several special hormones, such as secretin, formed in the walls of the small intestine, and cholecystokinin, formed in the mucosa of the duodenum; fatty substances, such as the fats of milk and eggs, stimulate contraction and evacuation of the gallbladder.
Some metabolic products, toxins, and medications may be discharged along with the bile into the intestine. Preparations containing bile and bile acids (dehydrocholic acid, Decholin, allochol, and cholenzym) are used as bile-flow stimulating agents; preserved medicinal bile (with added ethyl alcohol and a preservative) is used externally as an analgesic and resorptive in arthroses, arthritides, bursitides, and radiculitides.
IA. O. OL’SHANSKII