Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Oestrone is rapidly taken up by isolated perfused rat liver (t 1/2 less than 2 min) to yield at least 10 metabolites excreted in the bile; peak concentration occurs after about 20 min. 2. Sulphated metabolites of oestrone appear in the perfusate, reaching peak concentration at about 10 min, and then slowly disappear. 3. Sulphated metabolites of oestrone accumulate in the liver during the first 10 min. They are partly converted to sulphoglucuronides (steroid 3-sulphates conjugated with glucuronic acid in the D ring) and partly hydrolysed to be reconjugated as glucuronides. 4. The major biliary metabolites of oestrone in isolated perfused rat liver are glucuronides and sulphoglucuronides, but free steroids, sulphates and polar metabolites are also so excreted. 5. The isolated perfused guinea pig liver also rapidly takes up oestrone (t 1/2 less than 2 min) but, in contrast to the rat, a single glucuronide is the only quantitatively important metabolite in the bile: it is also extensively secreted into the perfusate where it reaches peak concentration at about 10 min. 6. In perfused guinea pig liver, oestrone does not form sulphoglucuronides, and sulphates are only minor metabolites; this is not due to lack of the appropriate sulphotransferase because oestradiol 17 beta-(beta-D-glucuronide) is extensively sulphated in this system. 7. Oestradiol 17 beta-(beta-D-glucuronide) is not cholestatic in the isolated perfused guinea pig liver although it is in rat liver. 8. There is a similar species difference in the metabolism of dehydroepiandrosterone in the two species: the rat forms sulphoglucuronides, the guinea pig does not. 9. The perfused rat liver extensively hydroxylates, presumably on the D ring, 17-deoxyoestrone and 17-deoxydehydroepiandrosterone. 10. The inability of perfused guinea pig liver to form sulphoglucuronides from oestrone or dehydroepiandrosterone is probably due to its restricted ability to hydroxylate the D ring of steroids. 11. Both rat and guinea pig biles contain beta-glucuronidase, about 80 and 230 sigma units/ml, respectively.
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PMID:The metabolism of oestrone and some other steroids in isolated perfused rat and guinea pig livers. 296 41

1. [4-(14)C]Oestradiol was administered to seven male, seven female and two castrated male cats as a single intravenous injection. Bile and urine were collected for 6h. 2. The radioactivity was excreted mainly in the bile of all animals (53-60%); only approx. 1% of the dose appeared in the urine. 3. Bile and urine samples were hydrolysed successively by beta-glucuronidase, cold acid and hot acid. There were significant differences (P<0.005) between the percentage of the dose present in the bile fractions hydrolysed by beta-glucuronidase (male, 9.0+/-1.7%; female, 18.6+/-1.45%) and by cold acid (male, 18.9+/-1.44%; female 12.1+/-1.02%). The excretion of radioactivity in these fractions by the castrated male cats was closer to that of female cats. 4. Approx. 20-27% of the dose could not be extracted from aqueous solution (pH10.5) by ethyl acetate-ether after hydrolysis.
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PMID:Steroid metabolism in the cat. Biliary and urinary excretion of metabolites of [4-14C] oestradiol. 542 33

Estrogen metabolism was studied in a newly established cell line (RL95-2) derived from a human endometrial carcinoma. Estradiol and estrone were metabolized to water-soluble derivatives by cells under in vitro culture conditions. Between 80-90% of the added steroids were metabolized, with nearly quantitative recovery of the products from the incubation medium. Arylsulfatase treatment converted the metabolites to ether-soluble forms, whereas beta-glucuronidase had no effect on the aqueous solubility of these compounds. Butanol extracts of the water-soluble estradiol metabolites cochromatographed on high performance liquid chromatography with 17 beta-estradiol-3-sulfate (93.6%) or estrone-3-sulfate (3.5%). No more than 6% of the estradiol added to the incubation medium was recovered in the form of estrone, either as estrone or estrone sulfate. After arylsulfatase treatment of the estradiol conjugates, 92% of the ether-soluble radioactivity cochromatographed with estradiol, and 3.8% cochromatographed with estrone. Estrogen-sulfurylating activity was localized in the cytosol of subcellular fractions of RL95-2 cells. The sulfoconjugation of estrogens by RL95-2 cells may prove useful as a model for the investigation of estrogen metabolism in endometrial carcinoma cells.
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PMID:Estrogen sulfoconjugation by human endometrial cancer cells (RL95-2) in culture. 669 41

The diameters of Sudan Black B stained sebum vesicles and acid hematein stained perinuclear granules, and the numerical density of the latter, were determined in mature sebaceous preputial cells from normal male and female rats, testosterone-treated female rats and estradiol-treated male rats. Statistical analysis by Student's t-test showed that the diameter of lipid droplets was significantly higher in male than in female controls and that testosterone increased female values up to make control levels. Estradiol treatment decreased male values to levels below those of normal male and female controls and of testosterone-treated female rats. Diameters of perinuclear granules did not vary among animal groups but their numerical density was larger in testosterone treated than in normal female rats or estradiol treated male rats. Lipid droplet sizes and perinuclear granule numbers are thus increased by androgens and decreased by estrogens, which was interpreted an meaning that sexual hormones do not only act on sebaceous cell multiplication or turnover time as previously known, but also on the production of lipid and the output of beta-glucuronidase containing granules in this gland.
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PMID:The effect of sexual hormones on the lipid and proteinaceous secretion of the rat preputial sebaceous gland. 727 16