Bile acids pigments

Lipids have been dehned on the basis of their stmctnre and solnbility. Lipids are natnrally occnrring componnds consisting of fatty acids and their derivatives, bile acids, pigments, vitamins, and steroids, as well as terpenoids, which are usually soluble in organic solvents such as benzene, chloroform, ether, and alcohol, etc., with variable solubility depending on the stmctnre of the lipid compound. 

Bile. The liver forms a thin secretion (bile) that is stored in the gallbladder after water and salts have been extracted from it. From the gallbladder, it is released into the duodenum. The most important constituents of bile are water and inorganic salts, bile acids and bile salts (see p. 314), phospholipids, bile pigments, and cholesterol. Bile salts, together with phospholipids, emulsify insoluble food lipids and activate the lipases. Without bile, fats would be inadequately cleaved, if at all, resulting in fatty stool (steatorrhea). Resorption of fat-soluble vitamins would also be affected. 

The cholesterol excreted with the bile is poorly water-soluble. Together with phospholipids and bile acids, it forms micelles (see p. 270), which keep it in solution. If the proportions of phospholipids, bile acids and cholesterol shift, gallstones can arise. These mainly consist of precipitated cholesterol (cholesterol stones), but can also contain Ca " salts of bile acids and bile pigments (pigment stones). 

Contraindications Allergy to bile acids, calcified cholesterol stones, chronic hepatic disease, radiolucent bile pigment stones, radiopaque stones... 

Verschure et al. (VI) have demonstrated by paper electrophoresis that in gall bladder bile the pigments form part of a lipoprotein complex to which cholesterol and bile acids are also bound. In hepatic bile this complex is not found in appreciable amounts, and the bile pigments are bound to two separate proteins. 

Although bile contains pigments, cholesterol, fatty acids, some sugars and bile salts, it is these last which are of particular importance to the physiology of cestodes. 

Endogenous clearance excretes physiological metabolites in a timely manner and in quantitatively appropriate proportions (e.g. bilirubin, enzymes, bile pigments, bile acids). 

Enzymatic activity 2. Synthesis capacity 3. Excretion capacity GPT, y-GT — ChE, — Quick s value AP, bile pigments — in the urine GOT, GDH — albumin — bilirubin, LAP — LDH ammonia, galactose EC bile acids, iron, copper, cholesterol, indocyanine green, LPX... 

Biochemically, a change in structure relating to the mucopolysaccharides (neuraminic add ) and monohydroxy bile acids probably accounts for the formation of biliary thrombi. Some of the under-hydroxylated bile salts appear in crystalline form the bile becomes increasingly viscous and its flow is impeded. This defect in the excretion of bile salts culminates in dysfunctions in the secretion of bilirubin, which is why bilirubin is regurgitated into the blood. The bile which accmnulates in the bile ducts ultimately becomes mucous and white because of the reabsorption of bile pigments by the epitheha of the small bile ducts. 

Determination of total bilirubin with differentiation between direct (conjugated) and indirect (unconjugated) bilirubin Determination of cholestasis-indicating enzymes (AP, LAP, y-GT) bile acids and bile pigments in the urine (s. tab. 12.6) Test for signs of haemolysis (s. tab. 12.3)... 

The biochemistry of the acids has really yet to be explored. However, certain aspects of their comparative biochemistry have been noted already, by implication rather than by discussion. It is evident that the variations observed, not only in the nature of the acid actually present but also in the quantities found in any one given source, reflect at a biochemical level an aspect of differentiation between animal species. Other such instances which might be cited are rather few, hut include the nature of the bile acids, phosphagens, and visual pigments. ... 

Hundreds of applications have been mentioned in the Zweig (1968) review acids, alkaloids, amino acids, antibiotics, antioxidants, food and feed additives, bases and amines, bile acids, carbonyls, dyes, enzymes, lipids, hydrocarbons, hormones, indoles, natural products, peptides, proteins, pesticides, plant growth regulators, pharmaceutical products, phenols, pigments (chlorophylls, xanthophylls, porphyrins, melanin, pterins, pteridines, anthocyanins, ilavonoids, etc.), polymers, purine and pyrimidine derivatives, quinones, RNA, DNA, organic sulfur compounds, steroids, sugars, toxins, vitamins, inorganic ions, and others. 

Shioda (82) investigated the effect of dietary constituents on gallstone formation in golden hamsters. Like Dam, he found that hamsters on a low-fat diet frequently formed cholesterol gallstones. The addition of unsaturated fats (codliver oil, sesame oil) prevented cholesterol stones but allowed the development of amorphous pigment stones. Cholesterol stones correlated well with increased cholesterol and decreased bile acids and phospholipids in hepatic bile that was consequently supersaturated with respect to cholester-... 

Early studies on the composition of cholestanol-induced gallstones established that they did not contain appreciable amounts of sterol (cholesterol or cholestanol) or pigment but consisted largely of glycine-conjugated bile salts (130,133,139,140). Mosbach and Bevans (139), utilizing cholestanol-14C, demonstrated that approximately half of the bile acids in the stones were... 

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