Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The distribution of glutathione (GSH), L-glutamic acid (Glu) and gamma-glutamyl transpeptidase (gamma-GT) was studied in bull reproductive organs and fluids. Glutathione, the physiological substrate of gamma-GT, was localized specifically by a fluorescence method in the testis, epididymis and spermatozoa. Of the reproductive tissues, the testis, caput epididymis and ampulla had the highest levels of GSH, but it was also present in seminal fluid. Washed caput epididymal sperm had three times the GSH content of cauda epididymal or ejaculated sperm. In spermatozoa, GSH displayed maximal staining in the midpiece and tail regions. The highest levels of gamma-GT were encountered in the epididymis. The concentration of Glu was also high in the epididymis. Its formation may be due to the hydrolytic activity of gamma-GT, which, in addition, may have an important role in the transfer of Glu residues to reactive groups on the sperm surface.
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PMID:Glutathione, L-glutamic acid and gamma-glutamyl transpeptidase in the bull reproductive tissues. 289 39

During postnatal development, gamma-glutamyl transpeptidase (gamma-GT), reduced glutathione (GSH), and L-glutamic acid (L-Glu) were assayed in the epididymides of rats at 5-day intervals between 10 and 60 days of age and compared to adult levels. gamma-GT activity (with gamma-glutamyl-p-nitroanilide as substrate) and L-Glu (nicotinamide adenine dinucleotide conversion-dependent assay) were measured photometrically, while GSH (o-phthalaldehyde reaction) was quantified with a fluorometric assay. In immature rats, the epididymal gamma-GT was very low but increased after 25 days of age in the caput and after 50 days of age in the cauda. The enzyme level in the epididymal caput was by far the highest in the adult rat reproductive tissues. The postnatal increase of gamma-GT in epididymal caput and cauda was associated with a decline of its substrate GSH and an accumulation of the product L-Glu. These observations provide evidence for the in vivo hydrolytic activity of gamma-GT and explain the high levels of L-Glu found in the epididymis of rats and other mammals.
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PMID:Gamma-glutamyl transpeptidase, glutathione, and L-glutamic acid in the rat epididymis during postnatal development. 290 Jun 57

Particles found in bovine seminal vesicle secretion were enriched by centrifugation. They varied in size and morphology and contained Mg2+,Ca2+-activated ATPase, aminopeptidase A, alanyl aminopeptidase, gamma-glutamyl transpeptidase and dipeptidyl peptidase IV activities. Hyperactivation of sperm motility and the acrosome reaction were induced by these particles in epididymal spermatozoa suspended in a modified Ringer medium. The hyperactivation, analysed with a microscopic slide test, started within minutes of exposure to membrane particles and continued for 3-4 h, during which time spermatozoa underwent the acrosome reaction. Acrosome staining, phase-contrast microscopy and transmission electron microscopy revealed that the acrosome reaction started within 60 min at 37 degrees C and affected up to 80% of spermatozoa in 4 h. These membrane particles differed from those reported previously in other species in enzyme composition, function and organ of origin.
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PMID:Effect of secretory particles in bovine seminal vesicle secretion on sperm motility and acrosome reaction. 357 75

The substrate specificity of rat testicular and epididymal peptidase was investigated using chromogenic substrates, D. L-alanine-, L-arginine-, gamma-N-L-glutamine-, L-leucine-, D. L-methionine-, alpha-N-benzoyl-D. L-arginine-, and N-benzoyl-L-leucine-beta-naphthylamide. The histochemical distribution of peptidase activity demonstrated with these substrates was also investigated in the testis and epididymis. L-Arginine-beta-raphthylamide (Arg-beta-NA) and gamma-N-L-glutamine-beta-naphthylamide (Glu-beta-NA) were mostly hydrolyzed in the testis and epididymis, respectively. Histologically, the activity using Arg-beta-NA as substrate (aminopeptidase B) appeared in both the cytoplasms and nuclei of interstitial cells and spermatogonia and the heads of spermatozoa, while activity using other substrates was found only in the cytoplasms of cells in the germinal epithelium. In the epididymis, strong reaction with Glu-beta-NA (gamma-glutamyl transpeptidase) was found in the apical part of the epithelial cells and in the heads of spermatozoa. Neither alpha-N-benzoyl-L-arginine- nor N-benzoyl-L-leucine-beta-naphthylamide was utilized in either the testis or the epididymis.
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PMID:Substrate specificity and histochemical distribution of aminopeptidase in rat testis and epididymis. 705 30

The expression of gamma-glutamyl transpeptidase (GGT) mRNA in tissues of the adult rat male reproductive tract was examined. Northern blot analysis of total RNA revealed that GGT mRNA expression occurs primarily in the initial segment and caput epididymidis. Multiple GGT mRNAs of varying sizes were detected in the testis and in different regions of the epididymis: testis, 2.4 and 2.8 kb; efferent ducts, 2.2 and 2.5 kb; initial segment, 2.2, 2.4, and 2.5 kb; caput, 2.2, 2.4, and 2.5 kb; corpus, 2.2 and 2.5 kb; cauda, 2.2 and 2.5 kb; ductus deferens, 2.2 and 2.4 kb. Ribonuclease (RNase) H removal of the poly(A) tail from testicular and epididymal GGT mRNA revealed that multiple GGT mRNAs were not generated by differences in the length of the poly(A) tail. Northern blot analysis of poly(A)+ mRNA with four GGT mRNA 5' untranslated region (UTR)-specific cRNA probes showed that the multiple GGT mRNAs expressed in the testis and epididymis were due to differences in the lengths and nucleotide compositions of the 5' UTR. We hypothesize that transcription of multiple GGT mRNAs from different promoters on the single-copy GGT gene is the molecular basis that underlies the region-specific expression of GGT mRNAs along the rat male reproductive tract.
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PMID:Multiple forms of gamma-glutamyl transpeptidase messenger ribonucleic acid are expressed in the adult rat testis and epididymis. 790 29

Multiple gamma-glutamyl transpeptidase (GGT) messenger RNAs (mRNAsII-IV) are expressed in a region-specific manner in the rat epididymis. In the present study, we examined the role(s) of plasma testosterone (T) and testicular factors in regulating the region-specific pattern and quantity of GGT mRNAs expressed along the epididymal duct. Northern blot and ribonuclease protection analyses showed that bilateral orchiectomy for 1, 5, and 15 days dramatically reduced the expression of GGT mRNAsII-IV in the initial segment. Expression of GGT mRNAII and mRNAIII was maintained in the initial segment of orchiectomized animals receiving T implants that maintain normal serum T concentrations, but GGT mRNAIV expression remained low relative to sham-operated control values. Unilateral efferent duct ligation decreased GGT mRNAIV expression only in the initial segment. Hence, expression of GGT mRNAIV in the initial segment was not maintained by circulating T and required a factor(s) of testicular origin. In caput epididymidis, expression of GGT mRNAII and mRNAIII declined after orchiectomy and was not completely restored to control values in orchiectomized animals by plasma T alone, but also required a testicular factor(s). In contrast to the initial segment, expression of GGT mRNAIV in the corpus and cauda epididymidis did not require T and/or a testicular factor(s), as expression of this transcript remained unchanged in these regions after 1, 5, and 15 days of orchiectomy, orchiectomy and T replacement, and after unilateral efferent duct ligation. In the cauda epididymidis, expression of GGT mRNAII required circulating androgens and was unaffected by unilateral efferent duct ligation, whereas GGT mRNAIII expression was repressed by T. These data demonstrate that circulating T and a factor(s) of testicular origin differentially regulate the expression of each GGT mRNA in a region-specific manner.
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PMID:Expression of multiple gamma-glutamyl transpeptidase messenger ribonucleic acid transcripts in the adult rat epididymis is differentially regulated by androgens and testicular factors in a region-specific manner. 791 28

1. The toxic manifestations of dermally applied hexachlorocyclohexane (50 mg or 100 mg kg-1 body weight day-1, 5 days in a week for 120 days) on testes and sperm of rat have been investigated. 2. The results indicate that exposure of HCH through the dermal route could lead to an alteration in the activities of marker testicular enzymes viz. sorbitol dehydrogenase (SDH), glucose-6-P-dehydrogenase (G6PDH), gamma-glutamyl transpeptidase (gamma-GT) and beta-glucuronidase (beta Gluc.) associated with specific cell types. 3. Significant quantities of HCH and its isomers accumulated in testes as well as sperm of treated rats. 4. HCH exposure also led to a decrease in serum testosterone levels, epididymal sperm count, sperm motility and an increase in the percentage of abnormal sperm. 5. These observations indicate the possibility of adverse effects of HCH on the male reproductive functions of men exposed dermally to this pesticide in industry or during spraying in the field.
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PMID:Effect of dermal application of hexachlorocyclohexane (HCH) on male reproductive system of rat. 851 23

1. Carbofuran was administered orally to adult male rats at dose levels of 0.1, 0.2, 0.4 or 0.8 mg kg-1 body weight, 5 d wk-1 for 60 days. A dose dependent decrease was observed in body weight of rats treated with 0.2-0.8 mg carbofuran kg-1 body weight. 2. A significant decrease in the weight of epididymides, seminal vesicles, ventral prostate and coagulating glands was observed at various test doses of carbofuran except at the lowest dose. 3. Decreased sperm motility, reduced epididymal sperm count along with increased morphological abnormalities in head, neck and tail regions of spermatozoa were observed in rats exposed to 0.2, 0.4, or 0.8 mg carbofuran kg-1 body weight. 4. In addition, significant alterations were observed in the activities of marker testicular enzymes viz. sorbitol dehydrogenase (SDH), glucose-6-P-dehydrogenase (G6PDH) (decreased), lactate dehydrogenase (LDH) and gamma-glutamyl transpeptidase (gamma-GT) (increased) depending on dose. 5. Histologically, the results indicated the toxicity of carbofuran on testes depending on dose. The changes predominantly consisted of moderate oedema, congestion, damage to Sertoli cells and germ cells, along with the accumulation of cellular debris and presence of giant cells in the lumen of a few seminiferous tubules which showed disturbed spermatogenesis with the higher doses of carbofuran. 6. These observations determined a no effect level dose of 0.1 mg kg-1 body weight of carbofuran on the biochemical and morphological indices studied for male reproductive toxicity assessment in the rat model. The results of the present study provide first hand information on the reproductive toxicity of carbofuran in male rats.
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PMID:Effect of oral administration of carbofuran on male reproductive system of rat. 858 50

Carbaryl was orally administered to male albino rats at 50 mg or 100 mg carbaryl/kg body weight 5 d/w for 90 d. A significant decrease in weight gain was observed at the high dosage after 60 d. Although no significant changes in the weight of testes, epididymides and accessory sex organs occurred, moderate to marked histopathological changes in the testes were seen at both dosage levels. Testicular enzymes associated with post-meiotic spermatogenic cells (sorbitol dehydrogenase) decreased, while lactate dehydrogenase increased concomitant with the observed degeneration of spermatogenic cells. Enzymes associated with pre-meiotic spermatogenic cells or Sertoli cells (gamma-glutamyl transpeptidase) increased, while glucose-6-phosphate dehydrogenase decreased. These effects were dose related and associated with declines in epididymal sperm count and percent sperm motility and increased abnormal sperm morphology.
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PMID:Effects of carbaryl on the rat's male reproductive system. 859 26

The objective of this study was to test the hypothesis that gamma-glutamyl transpeptidase (GGT) catalytic activity and protein level in the initial segment are regulated by testicular factors. In the rat epididymis, levels of GGT catalytic activity were initial segment > caput > corpus = cauda. GGT catalytic activity and protein level in the initial segment decreased after efferent duct ligation (EDL) for 3 days, but were recovered when initial segment pieces were incubated with ovine or rat rete testis fluid (oRTF or rRTF, respectively). Factors responsible for the recovery were shown to be greater than 10 kDa and protein-like, but these factors were not androgen-binding protein or testosterone in oRTF. Further experiments were designed to test the hypothesis that growth factors within oRTF and rRTF regulate GGT catalytic activity and GGT protein level. Basic fibroblast growth factor (bFGF) but not epidermal growth factor recovered GGT catalytic activity and protein level in the initial segment following 3-day EDL. Western blot analyses also revealed that bFGF-like proteins were present in rRTF, epididymal luminal fluid, and rat initial segment homogenate, and that the level of bFGF-like proteins declined in the initial segment following 3-day EDL. Using a bFGF monoclonal antibody, a small amount of bFGF-like proteins was found to be also present in oRTF. Our studies suggest that bFGF is one of the testicular factors involved in the regulation of epididymal GGT catalytic activity and protein level. Since decreased GGT catalytic activity caused by 3-day EDL in the rat initial segment was also recovered by a tumor promoter, phorbol 12-O-tetradecanoylphorbol 13-acetate, it is possible that a signal transduction pathway is involved in the regulation of GGT catalytic activity and GGT protein level by testicular factors. Western blot analyses also indicated that the 43-kDa bFGF-like protein in the lumen of the rat epididymis originates from the testis, is concentrated in the initial segment, and is reabsorbed by the epididymal epithelia from proximal to distal epididymal regions.
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PMID:Regulation of gamma-glutamyl transpeptidase catalytic activity and protein level in the initial segment of the rat epididymis by testicular factors: role of basic fibroblast growth factor. 947 41


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