Benders'dictionary of nutrition and food technology

114cholecystokinin (CCK) Peptide hormone secreted by the I-cellsof the duodenum in response to partially digested food enteringfrom the stomach. Stimulates contraction of the gall bladder,secretion of bile, secretion of pancreatic enzymes. Also stimulatescontraction of the pyloric sphincter, and so controls the rateof gastric emptying. Also known as pancreozymin.cholelithiasis See gallstones.choleretic An agent that stimulates the secretion of bile.cholestasis Failure of normal amounts of bile to reach the intestine,resulting in obstructive jaundice. May be caused by bilestones or liver disease.See also bilirubin, biliverdin.cholesterol The principal sterol in animal tissues, an essentialcomponent of cell membranes and the precursor for the formationof the steroid hormones. Not a dietary essential, since it issynthesised in the body.Transported in the plasma lipoproteins. An elevated plasmaconcentration of cholesterol in low-density lipoprotein is a riskfactor for atherosclerosis. The synthesis of cholesterol in thebody is increased by a high intake of saturated fats, but apartfrom people with a rare genetic defect in the regulation of cholesterolsynthesis, a high dietary intake of cholesterol does notaffect the plasma concentration, since there is normally strictcontrol over the rate of synthesis.See also hmg coa reductase; hypercholesterolaemia; hyperlipidaemia;lipoproteins, plasma.CHOLESTEROLcholestyramine Ion-exchange resin used to treat hyperlipidaemiaby complexing bile salts in the intestinal lumen and increasingtheir excretion, so increasing the metabolic clearance ofcholesterol.cholic acid One of the primary bile salts synthesised in the liverand secreted in the bile as a glycine or taurine conjugate.choline N-Trimethylethanolamine, a derivative of the amino acidserine; an important component of cell membranes.