Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0008370 (cholestasis)
 9,378 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of phalloidin, an agent that causes irreversible polymerisation of actin into microfilaments, on bile secretion and hepatocyte ultrastructure was examined in rats. Phalloidin was given intraperitoneally at the dose of 50 microgram per 100 g of body weight per day for 1, 3, or 7 days. The following was observed. (1) Bile flow decreased, as compared to controls, by 19% after 1 day, 34% after 3 days, and 55% after 7 days. Bile acid secretion was also decreased. (2) Electron microscopic examination of the hepatocyte in treated animals revealed an increased thickness of the pericanalicular microfilamentous network and a dilatation of bile canaliculi. Stereological examination revealed an increase in the relative volume of the microfilamentous network (per unit of hepatocyte cytoplasm) of 2.55% after 1 day, 4.06% ater 3 days, and 6.16% after 7 days. (3) [14C]Erythritol biliary clearance, measured after 7 days, decreased in parallel to bile flow, suggesting that the decrease in bile flow was of canalicular origin. [14C]Sucrose biliary clearance increased in treated animals, suggesting an increased permeability of the biliary system to sucrose. There was a predominant decrease in the bile acid independent bile flow. These data provide circumstantial evidence for the hypothesis that microfilament dysfunction can produce cholestasis.
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PMID:Phalloidin-induced cholestasis in the rat: relation to changes in microfilaments. 68 May

Sugar absorption by the biliary ductular epithelium under steady-state conditions was examined using isolated perfused rat liver. The test sugar and mannitol (as a putative marker of paracellular entry) were added to the glucose-free recirculating perfusate each at a concentration of 5 mmol/L, and apparent active biliary ductular absorption equated with the change in concentration of the test sugar relative to that of mannitol. A metabolizable hexose (D-glucose), pentose (D-xylose), and three nonmetabolizable hexoses (alpha-methyl-glucoside, 3-o-methyl-glucose, and L-glucose) were used. All five monosaccharides were well absorbed at constant rates for 2 hours with apparent rates of absorption (mumol.kg body weight-1.min-1, mean +/- SE) of D-glucose, 0.24 +/- 0.01; L-glucose, 0.20 +/- 0.02; 3-o-methyl-glucose, 0.19 +/- 0.02; alpha-methyl-glucoside, 0.16 +/- 0.03; and D-xylose, 0.10 +/- 0.04. The addition of phloridzin to the perfusate inhibited D-glucose absorption in part but did not inhibit L-glucose absorption. When perfusate Na+ was replaced by N-methylglucamine, the bile-plasma ratio of mannitol remained unchanged, as did the apparent absorption rate of D-glucose and 3-o-methyl-glucose. In contrast, absorption of L-glucose and alpha-methyl-D-glucoside gradually ceased. The addition of 15 mmol/L glucose to the perfusate caused decreased bile flow and increased taurocholate concentration in bile, suggesting that glucose absorption by the biliary ductules induced water reabsorption. It is concluded that sugars are absorbed by the biliary ductular system by Na(+)-dependent and Na(+)-independent transport systems, the substrate affinities of which differ from those reported for apical membrane hexose transport systems in renal tubular and intestinal epithelia. Ductular absorption of solutes such as glucose that enter bile passively may have biological use, because ductular absorption decreases the concentration of substrates for bacterial growth in gallbladder bile. On the other hand, ductular absorption of solutes induces reabsorption of biliary water, resulting in decreased bile flow; this might contribute to cholestasis during prolonged hyperalimentation with solutions containing glucose.
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PMID:Sugar absorption by the biliary ductular epithelium of the rat: evidence for two transport systems. 158 53

Oral administration of the HIV protease inhibitor L-689,502 caused cholestasis and hepatocyte injury in rats and dogs. These changes occurred rapidly, with elevations in serum transaminase observed as early as 6 hr after oral dosing in dogs. The acute phase of this hepatotoxic response was characterized in more detail in rats. Following intravenous administration, bile flow was decreased in a dose-dependent manner with greater than 90% decrease in less than 30 min at a dose of 5 mg/kg. The decrease in bile flow was associated with a decrease in erythritol clearance. The decrease in bile flow was not due to disruption of biliary tight junctions. Sucrose clearance was not increased and biliary bile acid concentrations in treated animals were not different from controls. Unlike control animals, bile flow was not stimulated by infusion of the bile acid tauroursodeoxycholic acid in animals treated with L-689,502. These cholestatic effects may be due, in part, to direct hepatocyte injury. Histological examination of perfusion-fixed livers 30 min after L-689,502 administration revealed periportal changes including hepatocyte vacuolation and occasional single cell necrosis. On a subcellular level, the nucleus and mitochondria were intact in less-severely affected cells. However, extensive vacuolation with multilamellar inclusions was pronounced in these cells. In addition, canalicular ectasia was also observed which was consistent with the cholestatic changes that were seen. In summary, L-689,502 is a potent, rapid acting hepatotoxin in dogs and rats. The mechanism by which this agent induces cholestasis is novel compared to other well-characterized cholestatic agents such as alpha-naphtylisothiocyanate and ethinyl estradiol.
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PMID:Hepatotoxicity of an HIV protease inhibitor in dogs and rats. 929 95

Increased gastrointestinal permeability has been demonstrated in several liver diseases. It may facilitate the absorption of gut-derived endotoxin-stimulating Kupffer cells to release proinflammatory cytokines or other potentially hepatotoxic compounds. We examined gastrointestinal permeability, plasma levels of anti-lipopolysacharides (anti-LPS), and four proinflammatory cytokines in 20 patients with intrahepatic cholestasis of pregnancy (ICP) compared with 22 normal pregnant and 29 non-pregnant women. Urinary excretion of sucrose and the urinary lactulose/mannitol (L/M) ratio after a standard oral load were used to assess gastrointestinal permeability. Anti-LPS (IgA, IgM, and IgG) were measured in peripheral blood by Human EndoCAb test kit; TNF-alpha, IL-1beta, IL-6, and IL-10 by Quantikine HS human immunoassays. Sucrose urinary excretion was similar in the three groups, indicating normal gastric permeability. The urinary L/M ratio was significantly higher in ICP than in the other groups [median (interquartile range): 0.018% (0.011-0.023) in ICP, 0.012% (0.009-0.016) in normal pregnancies, and 0.009% (0.008-0.012) in non-pregnant women, P < .01]. No significant differences were found in anti-LPS or cytokines plasma levels except slightly higher levels of IL-6 in ICP patients than in non-pregnant women (P < .05). Four of five women with abnormal urinary L/M ratio during ICP continued to show abnormalities in tests up to 2 years after delivery. In conclusion, an increased intestinal permeability was detected in ICP patients during and after pregnancy. A "leaky gut" may participate in the pathogenesis of ICP by enhancing the absorption of bacterial endotoxin and the enterohepatic circulation of cholestatic metabolites of sex hormones and bile salts.
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PMID:Is a leaky gut involved in the pathogenesis of intrahepatic cholestasis of pregnancy? 1655 65