Carp gallbladder

Centers for Disease Control and Prevention (CDC). Acute hepatitis and renal failure following ingestion of raw carp gallbladders—Maryland and Peimsylvania, 1991 and 1994. MMWR Morb Mortal Wkly Rep 1995 44(30) 565-6. 

Rung SW, Chan YC, Tse ML, Lau FL, Chau TL, Tam MK. Acute renal failure and hepatitis following ingestion of carp gallbladder. Clin Toxicol 2008 46(8) 753-7. 

Allen et al. (33) found no accumulation of the Thanite metabolite in gallbladder bile of carp exposed to 1 mg/1 of Thanite for 8 h at 12 C, nor could they detect the parent compound in any of the samples. The highest metabolite concentration (0.734 yg/g) was found in muscle samples taken immediately after exposure. 

The major bile salt of the carp, Cyprinm carpio, is 5a-cyprinol sulfate [21]. When [4- C]cholesterol was injected intraperitoneally into the carp, radioactive 5a-cyprinol was isolated from gallbladder bile [148]. It has been shown that the initial step in the major pathway for the formation of 5a-cyprinol (VI) from cholesterol (XV) is the 7a-hydroxylation of cholesterol to form cholest-5-ene-3j8,7a-diol (XVI) [149] (Fig. 4). It has also been shown that the double bond is isomerized to the A position before being reduced [150]. These in vivo studies suggest that until the intermediary formation of a A compound, presumably 7 ,12a-dihydroxycholest-4-en-3-one (XVII), the sequence of reactions in the biosynthesis of 5 -cyprinol (VI) in the carp is the same as that in the conversion of cholesterol (XV) to cholic acid (XIV) in mammals. 7a,12a-Dihydroxycholest-4-en-3-one (XVII) was found to be converted into 5a-cholestane-3a,7a,12a-triol (XVIII) by the microsomal fraction of carp hver fortified with NADPH [151]. The conversion of the triol (XVIII) to 5a-cyprinol (VI) via 27-deoxy-5a-cyprinol (XIX) was also established. The 26-hydroxylation of the triol (XVIII) was catalyzed by the microsomal fraction fortified with NADPH, and the 27-hydroxylation of 27-deoxy-5a-cyprinol (XIX) was catalyzed by the mitochondrial fraction fortified with NADPH [151]. 

To ascertain whether cholesterol is a precursor of 5a-cyprinol, Hoshita (133) administered C-cholesterol intraperitoneally to carp, in which 5a-cyprinol is the principal biliary sterol (134). After 12 days bile was collected from the gallbladder, and radioactive 5a-cyprinol corresponding to 0.14% of the administered sterol was recovered from bile. To ascertain whether choles-tanol or 7a-hydroxycholesterol was a precursor of 5a-cyprinol in this species Hoshita (58) administered these tritiated sterols intraperitoneally to carp and studied the distribution of in biliary constituents. From cholestanol-5,6- H, 1.1% of the biliary remained in the neutral fraction, of which 5a-cyprinol and 27-deoxy-5a-cyprinol were the major and minor constituents ( 22 1). Allocholic acid was the only radioactive component identified in the acid fraction. Two weeks after similar injection of 7a-hydroxycholesterol-7/S- H into carp, 17.6% of the radioactivity was recovered in bile, 86.5% of which was present in the neutral fraction and 6.3 % in the acid fraction. 5a-Cyprinol and 27-deoxy-5a-cyprinol ( 9 1) retained most of the tritium in the former fraction, whereas allocholic and cholic acids each retained ( 1.5 1) in the acid fraction. Thus, carp liver enzymes convert 7a-hydroxy-cholesterol to 5a sterols and to the 5/9- and 5a-C24 acids. Normally carp bile contains more cholic than allocholic acid. 

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