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)

Dipeptidyl carboxypeptidase (DC) is highly active in the testis and epididymis of rats and increases during pubertal development. Zinc deficiency during this period depresses the activity of DC in the testis. Experiments were conducted to determine the effects of zinc deficiency on epididymal DC activity. Comparisons were made between changes seen in this organ and those observed in testis. Three dietary treatments were used; zinc-deficient, fed ad libitum; zinc-adequate, pair-fed to the deficient group; and zinc-adequate, fed ad libitum. Results confirmed that testicular DC is affected negatively by zinc deficiency. DC activity was also lower in the epididymis of zinc-deficient rats than in control rats. These effects apparently were specific relative to changes in activity of other enzymes. Alkaline phosphatase activity in the epididymis was not affected by zinc deficiency and it was depressed in the testis. Gamma-glutamyl transferase activity in the epididymis was not affected by zinc deficiency but it was elevated in the testis. The results of this study suggest that part of the effect of zinc deficiency on sexual maturity in the male rat may be caused by reduced activity of DC. This enzyme is thought to be required for maturation and development of sperm cells.
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PMID:Zinc deficiency and dipeptidyl carboxypeptidase activity. Comparative effects on epididymis and testis of rats. 170 55

The tissular origin of alkaline phosphatase was evaluated in canine seminal plasma. Alkaline phosphatase activity was most concentrated in the first fraction of the split ejaculate and was virtually undetectable in the third and fourth fractions. By contrast, arginine esterase, a known marker of dog prostatic secretion, was present in similar concentrations in all fractions of the split ejaculates analyzed by SDS gel electrophoresis. Similarly, arginine esterase was very abundant in secretory granules prepared from dog prostate homogenates, whereas these granules contained virtually no alkaline phosphatase. Among male sex accessory organs, alkaline phosphatase activity was very high in the epididymis and much lower in the testis and prostate. Furthermore, the specific activity in epididymal fluid collected from the cauda epididymis was about 10 times higher than in the corresponding epididymal homogenates. These results show that the major portion of alkaline phosphatase in dog seminal plasma does not come from the prostate but from the epididymis.
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PMID:Origin of alkaline phosphatase of canine seminal plasma. 377 20

The activities of alkaline phosphatase and reduced nicotinamide adenine dinucleotide (NADH) diaphorase in the principal cells of the guinea pig epididymis were studied histochemically. Alkaline phosphatase activity was absent from the principal cells but was present in the basement membrane of the epididymal epithelium. NADH diaphorase activity was distributed throughout the cytoplasm of the principal cells in each epididymal segment. There was a gradual increase in NADH diaphorase activity from segments 1 through 7. Possible functions of alkaline phosphatase and NADH diaphorase in the epididymis are discussed.
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PMID:Localization of alkaline phosphatase and NADH diaphorase in the principal cells of the guinea pig epididymis. 668 19

Capillaries from freshly isolated rat epididymal fat were subjected to protocols that allowed ultrastructural localisation of alkaline phosphatase and 5'-nucleotidase. Alkaline phosphatase was almost entirely restricted to the capillary luminal membrane and vesicles associated with this membrane. 5'-nucleotidase was localised on the basal or abluminal membrane and associated vesicles. Arterioles and occasional venules were also present in the cell isolates, and arteriole localisation of 5'-nucleotidase was identical to that in capillaries. In venules, 5'-nucleotidase often failed to exhibit a polarised distribution and was present on both membrane domains. In confluent cultured endothelial cells, 5'-nucleotidase was not expressed in a predominantly polarised arrangement. Alkaline phosphatase was found on apical surfaces and regions of lateral cell contact. The results of these studies show that capillary endothelial cells exhibit enzyme polarity of their surface membranes which is subject to change on introduction of the cells to tissue culture.
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PMID:Apical-basal membrane polarity of membrane phosphatases in isolated capillary endothelium: alteration in ultrastructural localisation under culture conditions. 822 89

The assembly of the mammalian sperm flagellum is a complex developmental event requiring the sequential activation of genes encoding the component parts and the coordinated assembly of these proteins during the differentiation of the haploid spermatid. In this study, the mechanism underlying the assembly of the fibrous sheath surrounding the axoneme was examined. The subject of the study was the major fibrous sheath protein of the mouse sperm flagellum, AKAP82, a member of the A Kinase Anchor Protein (AKAP) family of polypeptides that bind the regulatory (RII) subunit of protein kinase A (PK-A). Immunoelectron microscopy demonstrated that AKAP82 is present throughout the transverse ribs and longitudinal columns of the fibrous sheath. Since AKAP82 is initially synthesized as a precursor (pro-AKAP82) during spermiogenesis, an antiserum was raised against a peptide from the processed region of pro-AKAP82 (M(r) 97,000). In immunoblotting experiments, the antibody detected pro-AKAP82 in condensing spermatids but not in epididymal sperm. In addition, two other immunoreactive proteins of M(r) 109,000 (p109) and M(r) 26,000 (p26, representing the "pro" domain of the precursor) were present in epididymal sperm. Alkaline phosphatase treatment of epididymal sperm proteins demonstrated that p109 was a phosphorylated form of pro-AKAP82 that remained in sperm. By immunofluorescence, pro-AKAP82 was localized to the entire length of the principal piece in testicular sperm, while in epididymal sperm p109 and p26 were present only in the proximal portion of the principal piece. Pro-AKAP82 was solubilized when germ cells were extracted with Triton X-100. However, in sperm, both AKAP82 and p109 were almost totally resistant to these extraction conditions and remained in the particulate fraction even after extraction with Triton and dithiothreitol. Similar to pro-AKAP82, the RII subunit of PK-A was present in the Triton X-100-soluble fraction of developing germ cells. In sperm, much of the RII also became particulate, consistent with the hypothesis that AKAP82 anchors RII in the flagellum. These data indicate that pro-AKAP82 is synthesized in the cell body, transported down the axoneme to its site of assembly in the fibrous sheath, and then proteolytically clipped to form mature AKAP82.
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PMID:Assembly of AKAP82, a protein kinase A anchor protein, into the fibrous sheath of mouse sperm. 944 72

1,3-Diphenylguanidine (DPG) has been used as a primary and secondary accelerator in the vulcanization of rubber. Exposure to 1,3-diphenylguanidine may occur as a result of dermal contact during rubber manufacture or from contact with the finished products. DPG is poorly absorbed through skin. Therefore, to evaluate the toxicity associated with systemic exposure, 2-week and 13-week toxicology studies were conducted by administering DPG in feed to groups of male and female F344/N rats and B6C3F1 mice. Genetic toxicity was also evaluated in Salmonella typhimurium and in the micronucleus erythrocyte assay in peripheral blood from male and female mice. During 2-week studies, rats and mice received feed containing 0, 250, 500, 750, 1,500, or 3,000 ppm 1,3-diphenylguanidine. All rats and mice survived to the end of the study. Feed consumption and mean body weights of groups of rats that received 750, 1,500, or 3,000 ppm were lower than controls. No compound-related gross lesions were observed at the end of the study. The final mean body weight of female mice that received 3,000 ppm was 6% lower than the controls at the end of the study; however, no other effects attributable to chemical exposure were observed in mice. Based on these results the same exposure concentrations (0, 250, 500, 750, 1,500, and 3,000 ppm) were selected for the 13-week study; because of the poor palatability of the 750 ppm or higher dosed feed in rats, concentrations greater than 3,000 ppm were not considered appropriate. Six male rats and all female rats that received feed containing 3,000 ppm died or were killed moribund before the end of the 13-week study. Final mean body weights and feed consumption of male and female rats that received 1,500 or 3,000 ppm were lower than controls throughout the study. The values of several hematologic parameters were significantly different from the controls in groups of rats that received 1,500 or 3,000 ppm; however, these differences were attributable to reduced nutrient intake as a result of reduced feed consumption. Lower total serum protein, cholesterol, triglyceride, and creatinine concentrations were also considered to be the consequence of reduced nutrient intake. Alkaline phosphatase activity and bile acid concentrations were greater than the controls in most groups exposed to DPG and were considered to be an indication of cholestasis. Secretory depletion of the seminal vesicles and prostate gland, epididymal hypospermia, spermatogenic arrest, and significant reductions in the absolute weights of the prostate gland, seminal vesicles, and testis were observed in male rats in the 3,000 ppm group. Uterine hypoplasia characterized by a reduction in uterine size due to thinner and less developed endometrium was observed in female rats that received diets containing 750 ppm or greater. The mean length of the estrous cycle was greater in female rats that received 750 or 1,500 ppm feed than in the controls. All mice survived to the end of the 13-week study. Mean body weights of males and females that received feed containing 750, 1,500, or 3,000 ppm were lower than the controls. Reduced organ weights relative to control for mice that received 1,500 or 3,000 ppm were related to low body weights of these groups. In mice that received 3,000 ppm sperm motility was reduced and the number of spermatid heads was greater than for control males, and the estrous cycle length in females was longer than that of the controls. 1,3-Diphenylguanidine was tested for mutagenicity in Salmonella typhimurium strains TA98, TA100, TA1535, and TA1537 with and without S9 metabolic activation enzymes. No mutagenic activity was observed in the absence of S9. With S9, positive responses were observed in strains TA98 and TA100, and an equivocal response was observed in strain TA1537. Results of a peripheral blood micronucleus test in B6C3F1 mice were concluded to be negative in males and equivocal in females. In summary, consumption of feed containing 1,3-diphenylguanidine for 2 weeks or 13 weeks was not associated with any histologic response which could be attributed to chemical exposure. Instead the observed changes were indicative of reduced nutrient intake and are consistent with similar changes observed in other studies of feed restricted rats and mice.
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PMID:Toxicity Studies of 1,3-Diphenylguanidine (CAS No. 102-06-7) Administered in Feed to F344/N Rats and B6C3F1 Mice. 1196 41

Alkaline phosphatase (AP) is a useful indicator of the presence of the sperm-rich (2nd) fraction in the canine ejaculate. Two AP isoenzymes originating from separate genes have been identified in the dog: tissue nonspecific (TNS) and intestinal. Bone, liver, and corticosteroid-induced AP are different isoforms of the TNS and intestinal isoenzymes. Using gel electrophoresis and levamisole inhibition assays, it was determined that seminal plasma AP (SAP) is a unique isoform of canine TNS AP whose glycosylation is distinct from either of the TNS AP isoforms commonly found in canine serum. Using immunocytochemistry, SAP activity was localized to the epididymal and seminiferous tubular epithelium. The ability to distinguish SAP from bone AP, liver AP and corticosteroid-induced AP could be beneficial to the practitioner in determining the quality of a semen sample.
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PMID:Characterization and localization of alkaline phosphatase in canine seminal plasma and gonadal tissues. 1274 43

Extracellular purinergic agonists regulate a broad range of physiological functions via P1 and P2 receptors. Using the epididymis as a model system in which luminal acidification is essential for sperm maturation and storage, we show here that extracellular ATP and its hydrolysis product adenosine trigger the apical accumulation of vacuolar H(+)-ATPase (V-ATPase) in acidifying clear cells. We demonstrate that the epididymis can hydrolyze luminal ATP into other purinergic agonists such as ADP via the activity of nucleotidases located in the epididymal fluid and in the apical membrane of epithelial cells. Alkaline phosphatase activity and abundant ecto-5'-nucleotidase protein were detected in the apical pole of principal cells. In addition, we show that nine nucleotidase genes (Nt5e, Alpl, Alpp, Enpp1, 2, and 3, and Entpd 2, 4, and 5), seven ATP P2 receptor genes (P2X1, P2X2, P2X3, P2X4, P2X6, P2Y2, P2Y5), and three adenosine P1 receptor genes (A1, A2B, and A3) are expressed in epithelial cells isolated by laser cut microdissection (LCM). The calcium chelator BAPTA-AM abolished the apical V-ATPase accumulation induced by ATP, supporting the contribution of P2X or P2Y in this response. The PKA inhibitor myristoylated protein kinase inhibitor (mPKI) inhibited adenosine-dependent V-ATPase apical accumulation, indicating the participation of the P1 A2B receptor. Altogether, these results suggest that the activation of P1 and P2 purinergic receptors by ATP and adenosine might play a significant role in luminal acidification in the epididymis, a process that is crucial for the establishment of male fertility.
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PMID:Role of purinergic signaling pathways in V-ATPase recruitment to apical membrane of acidifying epididymal clear cells. 2007 92