Akademik

A yellow bile pigment found as sodium bilirubinate (soluble), or as an insoluble calcium salt in gallstones; formed from hemoglobin during normal and abnormal destruction of erythrocytes by the reticuloendothelial system; a bilin with substituents on the 2, 3, 7, 8, 12, 13, 17, and 18 carbon atoms and with oxygens on carbons 1 and 19. Excess b. is associated with jaundice. [bili- + L. ruber, red]

- conjugated b. SYN: direct reacting b..

- delta b. the fraction of b. covalently bound to albumin; in conventional methods it is measured as part of conjugated b.. Because of its covalent bond during the recovery phase of hepatocellular jaundice it may persist in the blood for a week or more after urine clears.

- direct reacting b. the fraction of serum b. which has been conjugated with glucuronic acid in the liver cell to form b. diglucuronide; so called because it reacts directly with the Ehrlich diazo reagent; increased levels are found in hepatobiliary diseases, especially of the obstructive variety. SYN: conjugated b..

- indirect reacting b. the fraction of serum b. which has not been conjugated with glucuronic acid in the liver cell; so called because it reacts with the Ehrlich diazo reagent only when alcohol is added; increased levels are found in hepatic disease and hemolytic conditions. SYN: unconjugated b..

- b. UDPglucuronyltransferase (gloo-koo′ron-il-trans′fer-as) an enzyme that catalyzes the reaction of UDPglucuronate and b. forming UDP and b.-glucuronoside; a deficiency of this enzyme is associated with Crigler-Najjar syndrome.

- unconjugated b. SYN: indirect reacting b..

bil·i·ru·bin .bil-i-'rü-bən, 'bil-i-. n a reddish yellow pigment C₃₃H₃₆N₄O₆ that occurs esp. in bile and blood and causes jaundice if accumulated in excess

see bile pigments