Structure and Function of Bile. I. Relation between the Structure of Artificial Bile and Activity of Pancreatic Lipase

• Published in: Chemical & pharmaceutical bulletin Vol. 32; no. 9; pp. 3327 - 3336
• Main Authors: UEMATSU, SHOGO, UNNO, SETSUKO, NIIKURA, KAZUKO, SAWAUMI, TSUYOSHI, AKAHORI, YUKIO
• Format: Journal Article
• Language: English
• Published: Tokyo The Pharmaceutical Society of Japan 1984; Maruzen; Japan Science and Technology Agency
• Subjects: Analysis of complex biological substances; Analytical, structural and metabolic biochemistry; Bile - physiology; Bile Acids and Salts - analysis; Biological and medical sciences; Blood and biological fluids; Cholesterol - analysis; electron microscope; Fundamental and applied biological sciences. Psychology; In Vitro Techniques; Lipase - metabolism; Pancreas - enzymology; Phosphatidylcholines - analysis; Enzyme; Bile salt; Reconstituted system; Phosphatidylcholine; Triacylglycerol lipase; Lipids; Models; Cholesterol; Bile
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.32.3327

An aqueous solution of lecithin, bile salts, and cholesterol (artificial bile) which resembles human bile was studied by means of polarizing microscopy, electron microscopy, spin-probe electron spin resonance (ESR) spectroscopy, and pancreatic lipase treatment to digest fatty esters. The relation between the structure of artificial bile and the digestion of fatty esters by pancreatic lipase was investigated, and the following results were obtained. Artificial bile consists of bile salt micelles and bile salt-lecithin-cholesterol mixed micelles. Fatty esters are solubilized in these micelles. Lipase hydrolyzes fatty esters solubilized in bile salt micelles but not in bile salt-lecithin-cholesterol mixed micelles. Ranging from 0.1 to 0.4μ in size, the macromolecular complex of bile salt-lecithin-cholesterol can be observed by electron microscopy.