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)

Rat spermatozoa from the cauda epididymidis were found to have a lower activity of the surface ATPase than the spermatozoa from the caput region. The enzyme from spermatozoa of both regions had the same Michaelis constant (Km) for ATP of 5 X 10(-4) M. It was partly inhibited by ouabain and fluoride, but strongly inhibited by Cu2+, Zn2+,p-chloromercuribenzoate, 8-anilino-1-naphthalenesulphonate Triton X-100, Lubrol-PX, urea, guanidine hydrochloride, sodium dodecyl sulphate and glycerylphosphorylcholine. The enzyme of the spermatozoa from the cauda epididymidis was more sensitive to inhibition by ouabain and fluoride but less sensitive to inhibition by Cu2+ than that of the cells form the caput region. The Arrhenius plot of the temperature dependence of enzymatic activity varied for the cells from the caput and cauda epididymidis. The differences in the enzyme properties of spermatozoa from the two regions of the epididymis suggested that the decline in the activity during epididymal maturation may reflect changes in the lipids and sulphydryl groups of the sperm membrane.
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PMID:Changes in surface ATPase of rat spermatozoa in transit from the caput to the cauda epididymidis. 13 82

The zinc and copper content in the different epididymal segments and vas deferens of castrated rats were investigated with the help of atomic absorption spectrophotometer. The vas deferens showed maximum zinc content as compared to that of different parts of epididymis in all groups whether castrated unilaterally, bilaterally or in the intact control. Zinc content was reduced in the epididymis and vas deferens ipsilateral to the castrated side as compared to that of contralateral control and intake animals. Lowest zinc content was observed in the epididymis and vas deferens of bilaterally castrated animals from that of other groups. Absence of sperms was observed in all segments of epididymis and vas in bilaterally castrated animals and from the unilaterally castrated side. Copper content was unaltered in all epididymal segments and vas deferens. There appears to be a correlation between the absence of sperms in the male genital tract and the decrease in zinc content.
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PMID:Zinc and copper content in rat epididymis and vas deferens. 66 43

Changes in the concentration of -SH groups on the human and rabbit spermatozoal membrane and during epididymal maturation were studied by means of a new fluorescent probe, carboxyphenylmaleimide (CPhM), which reacts specifically with -SH groups. Binding of CPhM did not modify oxygen uptake, motility, or viability of the sperm cells used, but produced a characteristic increase in fluorescence. By analysis of this increase it was possible to calculate the presence of 35 +/- 4.2 and 55 +/- 8 nmoles of exposed -SH groups/10(8) rabbit and human ejaculated spermatozoa, respectively. Caput epididymal cells bound significantly more CPhM than did cauda epididymal cells or ejaculated spermatozoa (155 +/- 22, 78 +/- 11, and 35 +/- 4.2 nmoles/10(8) cells, respectively, in rabbit cells; and 184, 110 +/- 18, and 55 +/- 8 nmoles/10(8) cells, respectively, in humans cells). In addition to the differences in number of exposed -SH groups observed between human and rabbit sperm cells, the behavior of these membrane-reactive groups when ethylenediaminetetraacetate and/or zinc were added to the incubation media indicates that the participation of membrane--SH groups in sperm physiology is species-specific.
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PMID:Participation of membrane sulfhydryl groups in the epididymal maturation of human and rabbit spermatozoa. 100 33

The epididymal and seminal vesicular contributions to split-ejaculate fractions from boars were analysed for sperm concentration, glycerylphosphorylcholine (GPC), total-N, ethanol-soluble and insoluble N, citrate, zinc and haemagglutinin. The same components were also determined in epididymal plasma (EP), vesicular secretion (VS) and whole seminal plasma (SP). Isoelectric focusing of protein patterns was studied in the fractions. With the exception of haemagglutinin, the components were present to a major extent in either VS or EP and in lower concentrations in the other secretion. The parameters in VS or EP were positively correlated among themselves and negatively correlated with most of the parameters of the other fluid. The correlation coefficients were not significant in all cases for individual animals, but the degree of significance was greater for the over-all correlations. The EP components were mainly secreted in the first three or four fractions, but occasionally from fraction four onwards. Those of VS were emitted during the entire ejaculation, the maximum occurring in the sperm-rich fraction or the immediately succeeding fraction. The first fractions were devoid of VS components in only one case. The majority of the EP proteins could be identified electrophoretically in the sperm-rich fractions, but the protein patterns in the other fractions were similar to those of VS. The results are discussed and compared with previous findings.
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PMID:The split ejaculate of the boar: contributions of the epididymides and seminal vesicles. 112 18

1. The zinc content of rat spermatozoa increases, upon ejaculation, from 0.035 to 1.055 micrograms/10(6) cells. 2. The rat seminal plasma holds zinc both as free ion and as protein-bound forms. 3. Zinc-free ions bind in vitro to rat epididymal spermatozoa. 4. Zinc-protein complexes can be isolated, by a chromatographic procedure, from the dorsolateral lobe of rat prostate. 5. The isolated zinc-protein complexes bind in vitro to rat epididymal spermatozoa.
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PMID:Binding of free and protein-associated zinc to rat spermatozoa. 167 61

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

15 subjects with Hypogonadotropic Hypogonadism (HH) were treated with either gonadotropins (13 cases) or pulsatile subcutaneous Luteinizing Hormone Releasing Hormone (LHRH) (2 cases) for up to 42 months, to study the effects of therapy step by step. The following results were obtained: (A) In postpubertal HH (5 cases = Group A), therapy brought about onset of spermatogenesis within 3 months and its normalization within 6 months. In HH of prepubertal onset (10 cases = Group B), spermatogenesis started within 9 to 21 months and became normal in only 3 cases after at least 18 months. The best sperm counts were obtained in Group A in the third month of treatment (41.75 +/- 43.68 mil./ml) and in Group B in the 36th month (14.87 +/- 17.06 mil./ml). Sperm motility was normal in the majority of the cases in Group A from the beginning but did not become normal in Group B. (B) Seminal fructose and zinc were normal from the beginning of therapy in 66% of the cases in both groups. Zinc became normal in 100% within 3 months in Group A, in Group B within 18. Carnitine was normal in 50% of cases in both groups, contemporaneous with sperm appearance. Transferrin was normal in Group A after appearance of spermatozoa, but in Group B never became normal. (C) We hypothesize that the recovery of fertility passes through the following stages: (1) Functional recovery of Leydig cells, followed by seminal vesicles and prostate. (2) Recovery of epididymal function, which probably implies beginning of the tubular function. Recovery of Sertoli cell function occurs with more difficulty.
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PMID:Achievement of spermatogenesis and genital tract maturation in hypogonadotropic hypogonadic subjects during long term treatment with gonadotropins or LHRH. 177 42

The detection and the isolation of a zinc-protein from the secretion of the rat dorsolateral prostate is described. The purification procedure, based on gel filtration and cationic exchange chromatography, allowed to separate a minor protein (Mr approximately 66,000) from free zinc ions and other secretory components. Two zinc ions were estimated to be associated with one molecule of isolated protein. The zinc-protein was labelled with 125I and then incubated at 37 degrees C with spermatozoa from rat epididymal cauda. Time-dependent in vitro binding of the radioactive protein to sperm cells was demonstrated. This binding was not affected by the presence of proteins from the seminal vesicle during the incubation, while it was blocked in the presence of an excess of unlabelled zinc-protein. After binding, the labelled spermatozoa were treated with a buffer containing 0.5% sodium deoxycholate and 40 mM EDTA; only very small amounts of label were removed from the cells, thus suggesting that the zinc-proteins were kept on the plasma membrane by interactions which do not involve merely hydrophobic bonds.
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PMID:Zinc-protein from rat prostate fluid binds epididymal spermatozoa. 191 65

A protocol for the rapid purification of the glycerol dehydrogenase (glycerol: NAD+ 2-oxidoreductase, EC 1.1.1.6) from the thermophile Bacillus stearothermophilus has been developed using a combination of chromatographic techniques including affinity chromatography on a Sepharose-immobilised triazine dye (Procion red, HE3B, ICI). Substrate specificity has been examined and Km values determined. The protein has been shown to have an oligomeric Mr of approx. 180,000 and consists of four identical subunits of Mr 42,000. Exposure to chelating agents (e.g., EDTA) leads to total loss of activity; the EDTA-inactivated enzyme can be reactivated by Zn2+ and requires 1 mol equivalent of zinc per subunit for full catalytic activity. Other divalent cations such as Cd2+ and Co2+ will reactivate the apo-enzyme but yields an enzyme of lower specific activity. The enzyme binds 1 equivalent of NADH per subunit and during catalysis transfers the 4-pro-R hydride from the nicotinamide ring of the reduced-coenzyme to the substrate. Glycerol increases the dissociation constant for the interaction between NADH and Zn-metallo-glycerol dehydrogenase (ZnGDH) but has no effect on the equilibrium between NADH and metal-depleted enzyme.
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PMID:Isolation and characterisation of the glycerol dehydrogenase from Bacillus stearothermophilus. 249 67

In vitro binding of zinc to proteins of the human ejaculate and of the various male accessory gland secretions was evaluated. The proteins were separated by sodium dodecyl sulfate gel electrophoresis and transferred to nitrocellulose filters that were subsequently incubated with 65ZnCl2. High levels of zinc binding were observed to approximately 20 protein bands (14 to 70 kDa) of the coagulated seminal plasma. There was only low binding to proteins of the spermatozoa and virtually no binding to any protein of the epididymal and prostatic fluids. When sperm liquefaction was allowed to occur, 65ZnCl2 binding to high-molecular weight proteins decreased rapidly, and after 15 min only the binding to proteins of molecular weights less than 25 kDa remained. In addition, zinc concentration was determined both in the centrifugate and in the supernatant after centrifugation of the coagulum. Zinc concentrations in the centrifugate and the supernatant were, respectively, 147 +/- 72 micrograms/g and 31 +/- 22 micrograms/g. The whole supernatant contained only 12% +/- 4% of total sperm zinc. Finally, in highly viscous sperm samples the concentration of zinc was not significantly different from that in normally liquefying sperm (167 +/- 87 micrograms/ml compared to 188 +/- 107 micrograms/ml). The main extracellular targets of prostatic zinc in humans are the secreted seminal vesicle proteins. The role of this binding remains unknown, however, because no direct relationship could be established between the concentrations of this metal and the phenomena of coagulation and liquefaction.
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PMID:Zinc binding to major human seminal coagulum proteins. 258 9


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