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)

The histochemical localization of five glycosidases was studied in the epididymis of mature dogs. beta-Galactosidase showed a distinct to strong reaction in the epithelium of the ductuli efferentes and throughout the whole length of the ductus epididymidis. beta-N-Acetylglucosaminidase reactivity was weak in the initial segment, but increased significantly in the middle and terminal segment. The maximum beta-glucuronidase activity was found in the ductuli efferentes and in the initial segment. The alpha-mannosidase reaction was weak in all segments except the middle segment where a distinct activity was seen. With the method employed, no alpha-fucosidase activity could be detected. The physiological role of the glycosidases in the epididymis is discussed briefly.
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PMID:Histochemical localization of glycosidases in dog epididymis. 10 50

This article reports the application of Hayashi's histochemical technique for beta-glucuronidase to mouse epididymis. A methodological study, which established optimal conditions for demonstrating the enzyme in this organ, is reported. The distribution pattern of beta-glucuronidase is described and correlated with previous data for alpha-naphthyl acetate esterase. Differences between sites of granular and diffuse reaction product for these two enzymes are recorded. Possible interpretations of these findings in terms of intracellular localization of enzymes are discussed. Studies on different strains reveal regular differences in histochemical organization between mice of various genotypes. Histochemical data which imply androgen inducibility of beta-glucuronidase in mouse epididymis are preliminary noted.
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PMID:Histochemical studies on genetical control of hormonal enzyme inducibility in the mouse. III. Beta-glucuronidase distribution pattern of epididymis in different genotypes. 43 97

The influence of castration, androgen replacement therapy and cyproterone acetate on the activity of beta-glucuronidase, acid and alkaline phosphatases and glucose-6-phosphate dehydrogenase was studied in the caput, corpus and cauda epididymidis of the mouse. The results add further evidence that the epididymis is not uniform but has regional differences in activity. Thus beta-glucuronidase was found to be androgen-dependent only in the cauda epididymidis, whereas glucose-6-phosphate dehydrogenase was under androgenic control in the caput epididymidis. The response of alkaline and acid phosphatases to castration and to androgen replacement was different in different segments.
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PMID:Effects of castration, 5 alpha-dihydrotestosterone and cyproterone acetate on enzyme activity in the mouse epididymis. 51 8

The ability to form androgen conjugates and the hormone dependency of the conjugating enzymes have been studied in the rat epididymis. Following the in vitro incubation of 3H-testosterone with epididymal slices from intact and castrated rats, the radioactivity recovered was partitioned between water and ether. Examination of the water soluble radioactivity demonstrated the presence of glucuronides and sulfates. The total radioactivity in the conjugate fraction was the same for both intact and castrated animals. However, castrated rats showed a 3-fold increase in the glucuronide fraction with a corresponding decrease in the formation of sulfates. Characterization of the ether soluble radioactivity after solvolysis of the conjugate fraction from castrated animals, showed DHT (17beta-hydroxy-5alpha-androstan-3-one) and 3alpha-diol (5alpha-andro-stane-3alpha, 17beta-diol) to be the main metabolites. After beta-glucuronidase hydrolysis of the same, only 3alpha-diol could be demonstrated at a significant level, although traces of DHT and delta16 compounds were present. Corresponding hydrolysis of the water phase from incubation of epididymis from intact rats, demonstrated a marked quantitative difference. Here approximately 40% of the conjugated aglycones consisted of delta16 compounds, whilst only about 12% was comprised of 3alpha-diol. The preferential conjugation of DHT and 3alpha-diol to a sulfate radical was demonstrated in both intact and castrated rats. Since the conjugated delta16 compounds were detected only in the epididymis from intact animals, it is possible that these are formed by the spermatozoa.
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PMID:Androgen metabolism by rat epididymis. 4. The formation of conjugates. 94 Nov 82

Although it has been indicated that many neurotoxicants also cause reproductive toxicity, the reproductive toxicity of megadoses of pyridoxine, which is a neurotoxicant, has not been studied. In this paper, we studied the effects of megadoses of pyridoxine on male reproductive organs. Pyridoxine hydrochloride, 125 mg/kg, 250 mg/kg, 500 mg/kg or 1000 mg/kg, daily, was intraperitoneally injected into Wistar male rats 5 days a week for 2 or 6 weeks, and its effects on the male reproductive organs were investigated. After 2 weeks of administration, absolute weights of the testis in the 500 and 1000 mg/kg epididymis in all the exposed groups and prostate gland in the 1000 mg/kg group decreased, and mature spermatid counts in the testis decreased in the 1000 mg/kg group. After 6 weeks administration, the absolute and relative weights of the testis, epididymis, prostate gland and seminal vesicle decreased in the 500 mg/kg and 1000 mg/kg groups, and mature spermatid counts in the testis and sperm counts in the epididymis decreased in these groups. Among the marker enzymes of the testicular cells, LDH-X activity decreased, and beta-glucuronidase activity, cytochrome P-450 content and cytochrome b5 content increased in the 1000 mg/kg group. Plasma testosterone concentration did not significantly alter in all the exposed groups. From these results, it was concluded that megadoses of pyridoxine affected the spermatogenesis and decreased reproductive organ weights in the rat.
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PMID:Effects of megadoses of pyridoxine on spermatogenesis and male reproductive organs in rats. 149 84

The serum concentrations of FSH, LH, prolactin, testosterone, and estradiol and the enzymatic activities of hyaluronidase, glucosidases (alpha-glucosidase, beta-glucosidase, alpha-mannosidase, N-acetyl-beta-D-glucosaminidase, beta-glucuronidase, and beta-galactosidase), lactate dehydrogenase and its isoenzymes (LDH1, LDH2, LDH3, LDH-X, LDH4), and total proteins were measured in the semen of 69 subjects (8 normozoospermic controls, 7 secretory, and 54 excretory azoospermic subjects). FSH levels rose with the deterioration in spermatogenesis and served to differentiate the secretory from the excretory azoospermias. The only source of hyaluronidase and LDH-X in the ejaculate is the spermatozoa. alpha-Glucosidase activity essentially originates in the epididymis. The seminal determination of alpha-glucosidase and, to a lesser extent, alpha-mannosidase and N-acetyl-beta-D-glucosaminidase helps rapidly, sensitivity, reliably, and noninvasively to differentiate secretory azoospermias (with higher enzymatic activity) from the excretory type (less enzymatic activity) and may be of use in identifying with a certain degree of reliability the site of obstruction in the male genital tract.
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PMID:Enzyme and hormonal markers in the differential diagnosis of human azoospermia. 153 Mar 67

Flutamide, a pure antiandrogen, increases the levels of plasma luteinizing hormone but antagonizes the biological expression of androgen on target organs. Flutamide was administered to rats to study the effect of altered availability of hormones on the functional status of epididymis. The weights of ventral prostate, seminal vesicles and epididymis showed antiandrogenic effects of flutamide. However, increased activity of kidney beta-glucuronidase reflected increased availability of testosterone. The concentrations of protein and DNA along with the activities of acid phosphatase and hyaluronidase decreased in flutamide-treated rats. The activities of acid phosphatase and hyaluronidase in epididymal sperms along with protein concentration increased in flutamide-treated rats. Alteration of epididymal function by treatments affecting lysosomal stability was indicated.
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PMID:Effect of flutamide on the physiological status of epididymis and epididymal sperms. 160

During transit through the epididymis, spermatozoa acquire fertilizing the cell surface exhibits an altered glycoprotein pattern. Epididymal cells and their secretions contribute to these sperm-surface changes. To examine this process, epithelial cells from rat caput and cauda epididymidis were cultured and examined for the synthesis, processing and secretion of two glycoprotein-modifying enzymes, beta-galactosidase and beta-glucuronidase. Cells were cultured four days, incubated with D-2-[3H] mannose and L-[35S] methionine, and placed in isotope-free media. Levels of both cellular and secreted beta-galactosidase and beta-glucuronidase were determined by immunoprecipitation of cell homogenates or medium, followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and scintillation counting of bands. During a 1-h pulse, both caput and cauda cells synthesize two precursor forms of beta-galactosidase (Mr = 84,000 and 87,000), which are processed to the mature (Mr = 63,000) enzyme during a 24-h chase. Caput cells release a high molecular weight (HMW) form (Mr = 90-100,000) and mature beta-galactosidase into the media, but not the Mr = 84-87,000 precursor. On the other hand, cauda cells release mostly mature beta-galactosidase. Ratios of radiolabeled mannose/methionine demonstrate a 7-fold greater mannose content in the cellular precursor of beta-galactosidase than in total protein. Another glycosidase, beta-glucuronidase, is synthesized as a Mr = 78,000-precursor which is processed to the mature Mr = 72,000 form. Medium in which caput and cauda cells were cultured contains both mature enzyme and a Mr = 94,000 form, but no 78,000-precursor form. Ratios of radiolabeled mannose/methionine in the cellular precursor of beta-glucuronidase are 2-fold greater than ratios in the total glycoprotein. Secretion is the major pathway of turnover for several epididymal glycosidases, since more than 50% of the total is secreted/day. These results indicate that cultured epithelial cells from the epididymis synthesize glycosidases and that processing and release differ, depending on the enzyme and the epididymal segment from which the epithelial cells were isolated.
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PMID:Glycosidases in cultured rat epididymal cells: enzyme activity, synthesis and secretion. 309 Nov 1

Seven glycosidases (beta-N-acetylglucosaminidase, alpha-fucosidase, beta-galactosidase, acid alpha-glucosidase, beta-glucuronidase, acid and neutral alpha-mannosidase) were analysed in seminal plasma from the first and second successive ejaculates in normal Ayrshire bulls. In comparison to our previous data the results indicate that beta-N-acetylglucosaminidase, beta-galactosidase and beta-glucuronidase are derived mainly from epididymal secretions, while alpha-fucosidase and particularly neutral alpha-mannosidase originate additionally from the spermatozoan cytoplasmic droplets. The seminal vesicles appear to contribute particularly to the seminal plasma acid alpha-glucosidase and acid alpha-mannosidase activities. The seminal plasma enzymes derived from the epididymis and cytoplasmic droplets were suppressed in semen samples with low sperm density or with high numbers of abnormal spermatozoa. The epididymal and seminal vesicle enzymes could be utilized in assessment of the secretory/functional capacity of these glands.
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PMID:Comparison of glycosidase levels in bovine seminal plasma. 311 30

Each epididymis of control and swainsonine-fed rats (5 micrograms/ml drinking water) was divided into 5 segments, and tissue, spermatozoa and sperm-free supernatants were prepared from each segment. When levels of 3 lysosomal glycosidases and total protein were determined, the proximal cauda contained the greatest concentration of glycosidase. The specific-activity profile for beta-glucuronidase and beta-galactosidase was similar in swainsonine-fed and control rats. However, the concentration of alpha-D-mannosidase in tissue of all segments was significantly greater in swainsonine-fed rats than in age-matched controls. Enzyme activity for alpha-D-mannosidase after swainsonine treatment was significantly greater in spermatozoa from the caput, than in spermatozoa from the corpus and the cauda epididymidis. Since the alpha-D-mannosidase activity was optimal at pH 4.5 and studies with highly specific antibody to lysosomal alpha-D-mannosidase immunoprecipitated all of the alpha-D-mannosidase present in detergent extracts of epididymal tissue, spermatozoa, and sperm-free supernatant, the enzyme studied is of lysosomal origin.
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PMID:Effect of swainsonine on rat epididymal glycosidases. 314 32


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