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

Specific modification of the single lysine residue (Lys-12) in glucagon with O-methylisourea has been effected by blocking the reactivity of the amino terminal histidine with copper, providing a method for obtaining [12-homoarginine]glucagon. It was found that as a side reaction, under the conditions of the modification reaction, Cu(II) catalyzed cleavage of the polypeptide chain between Asp-9 and Tyr-10, and between Lys-12 and Tyr-13. This observation may be of value for development of a sequence-specific peptide cleavage procedure. The dilute solution conformations of glucagon and [12-homoarginine]-glucagon were compared by circular dichroism, fluorescence, phosphorescence, energy transfer, and optical detection of magnetic resonance. The results indicate that conversion of Lys-12 to homoarginine does not alter the helix content the side chain conformation in the vicinity of the tyrosine and tryptophan residues, or the relative distances and orientations between these residues. However, the modification reduces the hormone potency towards activation of lipolysis in isolated rat epididymal fat cells by a factor of seven. We attribute the loss of potency to an interference with a specific interaction between the lysine residue and the fat cell hormone receptor, and not to a change in the solution conformation of the hormone.
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PMID:[12-Homoarginine]glucagon: synthesis and observations on conformation, biological activity, and copper-mediated peptide cleavage. 42 94

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

This study was undertaken to determine whether a reduction in hepatic lipogenesis would be beneficial in the amelioration of copper (Cu) deficiency when fructose is fed. Garlic was chosen as the agent for reducing hepatic lipogenesis. Forty-eight weanling rats were fed Cu-deficient or adequate diets containing fructose or starch with or without garlic for 5 weeks. Garlic ameliorated the signs associated with Cu deficiency, although hepatic lipogenesis was not affected. Administration of garlic reduced the activity of the lipogenic enzyme glucose-6-phosphate dehydrogenase only in Cu-adequate rats. Consumption of garlic resulted in increased epididymal fat pad and pancrease sizes, and higher hematocrits, insulin and thyroxine concentrations. Mechanisms other than lipogenesis that could be responsible for this phenomenon are discussed.
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PMID:Garlic oil extract ameliorates the severity of copper deficiency. 161 86

1. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) produces atrophy, morphological changes, impaired spermatogenesis, and epididymal lesions in testis of experimental animals. The effects of TCDD administration to male rats on various parameters in the testes were examined. 2. Nine days after TCDD administration, significant decreases in body and testes weights occurred. However, the testes weight as a percent of body weight was higher in treated than control animals. 3. An increase in lipid peroxidation (content of thiobarbituric acid reactive substances) occurred in conjunction with the decrease in testicular weights. 4. TCDD administration produced a 3-fold increase in protein kinase C activity, small but significant decrease is superoxide dismutase and glutathione peroxidase activities, and no effect on catalase, glutathione reductase or glutathione S-transferase activities in the testes. 5. Nine days after treatment with TCDD, in the testes the iron content of whole tissue and cytosol increased while a decrease in microsomal iron was observed. The copper content of mitochondria and microsomes decreased with a corresponding increase in cytosol copper content. A small increase in the zinc content of whole testes occurred. 6. The data indicate that testicular atrophy due to TCDD may be associated with lipid mobilization and peroxidation.
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PMID:2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-induced alterations in lipid peroxidation, enzymes, and divalent cations in rat testis. 324 26

In male rats, a single injection of 10 mg metallic copper particles in oil into each caput epididymidis induced infertility, whilst leaving mating behaviour and blood testosterone levels unchanged. Fertility tended to recover 5.5 months after the copper treatment. Although the copper content of the caput epididymidis reached a level of around 100 times higher than control values, the serum copper concentration did not rise significantly. This finding and the observation that treated animals gained weight as fast as the controls suggest a low systemic toxicity of this method. The testicular copper concentration was significantly higher than that in controls and different degrees of damage, including vacuolation, karyorrhexis, pyknosis, and cytolysis, were seen mainly in pachytene spermatocytes and early spermatids. Clumps of foreign particles, apparently metallic copper, were found in the interstices of the caput epididymidis together with degenerative changes in the epithelial cells of the caput, suggesting a possible effect of copper on the epididymal epithelium. The viability of epididymal sperm decreased more markedly than the decrease in sperm density. It is therefore most likely that the major cause of infertility after copper injection into the caput epididymidis is a direct inhibitory effect of copper on the sperm, whilst damage to the seminiferous and epididymal epithelial may contribute.
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PMID:Effect of intra-epididymal injection of copper particles on fertility, spermatogenesis, and tissue copper levels in rats. 401 91

Rats fed a copper-poor diet were found to have a reduced plasma insulin response to an oral glucose load in comparison with rats fed a copper-supplemented diet. In addition, the increment in plasma glucose above the fasting level at 60 min and at 120 min was significantly higher in rats maintained on the copper-poor diets. In vitro glucose incorporation into diaphragm glycogen and into epididymal fat-pad lipids was stimulated greater than twofold by the addition of 100 micrograms/ml CuCl2 to the incubation medium. In tissues of streptozotocin-diabetic rats, the stimulatory effect of copper on glucose incorporation in vitro was also noted, but was significantly smaller. These results indicate that glucose utilization by peripheral tissues and insulin release may be added to the many vital functions for which copper is essential.
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PMID:Effect of copper on carbohydrate metabolism in rats. 621 23

The effects of copper and insulin on lipogenesis and glucose tolerance were studied using diabetic, copper-deficient rats. Diabetes was induced by intraperitoneal injection of 50 mg streptozotocin/kg body weight to rats fed a sucrose-copper deficient diet for 7 weeks. Five days later the rats were injected intraperitoneally with [14C]glucose with either saline, insulin, copper, or copper plus insulin. The disappearance of serum [14C]glucose at 30, 60, and 120 min postinjection and the incorporation of [14C]glucose into lipid of epididymal fat 2 hr after administration were determined. The combined effect of copper and insulin significantly decreased peak blood glucose at 30 min and increased the incorporation of [14C]glucose into lipid in the epididymal fat pad when compared to either copper or insulin alone. The enhancement of glucose utilization may be due to a formation of a more stable complex which will increase insulin binding and/or decrease its degradation.
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PMID:Effect of copper or insulin in diabetic copper-deficient rats. 634 92

Copper deficiency was induced in rats by feeding sucrose or starch diets deficient in copper. Copper-deprived rats fed either diet exhibited decreased plasma ceruloplasmin concentration and increased plasma cholesterol. Glucose homeostasis and utilization was impaired both in vivo and in vitro. Oral glucose tolerance was impaired, insulin binding decreased, and CO2 formation and lipogenesis from [U-14C]glucose were decreased. Feeding sucrose but not starch diets deficient in copper magnified the copper deficiency and resulted in 60% mortality. Although both deficient diets contained the same concentration of copper, the hepatic copper concentration of rats fed sucrose was reduced nearly threefold compared to rats fed starch. Reduced epididymal fat pad, increased liver weight, reduced blood hemoglobin and a marked hypertrophy of the heart with gross deformities as well as histopathologic changes were noted only in those rats fed the copper-deficient sucrose diet. The biochemical lesions induced by deprivation of copper can be suppressed by feeding diets containing starch or can be magnified by high sucrose intake.
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PMID:Effect of copper deficiency on metabolism and mortality in rats fed sucrose or starch diets. 634 33

One protein in canine seminal plasma accounts for over 90% of the total protein and is present at the high concentration of approximately 10 mg/ml. We demonstrate that this predominant protein is a proteolytic enzyme. The enzyme has been purified and migrates as a single symmetrical peak of apparent molecular mass of 29,000 daltons on a column of Sephadex G-75 and as a single band of approximately 30,000 daltons when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. Under reducing conditions, the enzyme dissociates into subunits of 15,000 and 12,000-14,000 daltons. The 15,000-dalton subunit contains the enzyme active site as determined by labeling with [3H]diisopropyl fluorophosphate. The enzyme hydrolyzed the synthetic ester substrates N alpha-benzoyl-L-arginine ethyl ester and N alpha-tosyl-L-arginine methyl ester with maximum specific activities at 25 degrees C of 105 mumol/min/mg and 33 mumol/min/mg, and Km values of 7.4 and 9.1 mM, respectively. The enzyme exhibited a pH optimum of 8.0. The metal ions, Cu2+, Zn2+, Cd2+, and Co2+ were reversible inhibitors and diisopropyl fluorophosphate and phenylmethanesulfonyl fluoride irreversible inhibitors of enzymatic activity. By immunofluorescence, the enzyme can be detected on the tail and postacrosomal regions of washed ejaculated canine sperm, but it is absent from epididymal sperm.
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PMID:The predominant protein of canine seminal plasma is an enzyme. 638


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