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 specific activities of three acid phosphatases were followed in the epididymis of growing rats. All activities were constantly rising but revealed two steeper parts probably corresponding to the increase of androgen secretion and the arrival of spermatozoa in the epididymis. Simultaneously an increase in the histochemical staining was obtained in all epididymal segments. Both biochemical and histochemical studies showed that castration reduced the activity of all acid phosphatases and this could be restored with testosterone-estradiol treatment. Estradiol had no effect on the activities in the castrated animal, but in the normal animal it caused an elevation of Enzyme I activity. In the histochemical study estradiol seemed to restore the acid phosphatase activity. Enzyme I reacted slower than the others to both castration and hormone treatment. Increased elimination caused by ligation of the epididymis caused a reduction in the activity of all enzymes within four days. It was greatest in the area of the corpus. This study, however, rendered no further elucidation for the assumption that acid phosphatases participate in the elimination of excessive and defective spermatozoa.
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PMID:Acid phosphatase of the rat epididymis. III. Histochemical and biochemical responses in experimental conditions. 59 63

morphologic comparisons of the live and dead sperm population gives information concerning non-lethal and lethal abnormalities. Many of the abnormalities of the sperm heads and midpieces and in particular enlarged heads belong to the latter group. On the other hand, tapering of the head, cytoplasmic droplets and abnormal tails have littel lethal significance. Depletion of the extra-gonadal sperm reserve does not affect the morphology of neither the living nor the dead spermatozoa. This indicates that no significant abnormalities develop after sperm maturation within the epididymis. Cyproterone acetate was shown to affect midpieces and fails of the living spermatozoa within two weeks of treatment indicating an effect on the epididymal level, whereas abnormal heads increase after four weeks indicating an effect on the germinative epithelium, not before the spermatid stage.
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PMID:On the development of different morphologic abnormalities of human spermatozoa. 62 12

A comparative light and electron microscopic study was done on cauda epididymal spermatozoa from +/tx, T/+, T/tx, C57BL/6J, BALB/c and randomly breeding Swiss Albino mice. The results show that all of the males contain abnormal spermatozoa and that all contain the same types of defective gametes. No unique defect was found which can be correlated with the increased transmission frequency of the tx-bearing allele.
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PMID:A study of spermatozoan defects in wild-type and T:t-bearing mice. 65 Jan 39

The fertilizing ability of testicular, epididymal, and ejaculated rabbit spermatozoa was evaluated in vitro following in vitro capacitation by high ionic strength treatment. Fewer than 11% of inseminated ova were apparently fertilized (i.e., in pronuclear, two-, and four-cell stages as determined by light microscopy) when testicular sperm treated with caffeine, caput epididymal, or corpus epididymal sperm samples were tested. A greater fertilizing ability, reflected by the percentage of ova fertilized and more normal progression of embryonic development, was exhibited by cauda epididymal sperm. Of 93 ova, 68 (73.1%) were fertilized by cauda sperm, whereas ejaculated sperm from the same 10 bucks fertilized 34 (36.6%) of 93 ova (P is less than 0.005). Ultrastructural examination of selected ova apparently fertilized by sperm from levels of the male reproductive tract proximal to the cauda epididymidis revealed abnormal activation. Authentic fertilization occurred when ova were inseminated with cauda epididymal and ejaculated sperm. An unusual and infrequent form of activation involving failure of cortical granule breakdown in ova penetrated by cauda epididymal and ejaculated sperm was seen. A comparison of fertilizing ability of sperm from first, second, and third ejaculates revealed a significant decrease with the third ejaculate (P is less than 0.01).
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PMID:In vitro fertilizing ability of testicular, epididymal, and ejaculated rabbit spermatozoa. 66 37

Fertilization of rat eggs in vitro could not be achieved when epididymal spermatozoa were preincubated and eggs in clots incubated in a chemically defined medium without D-glucose. Very high proportions (84-100%) of eggs examined were undergoing fertilization when 2.78-8.34 mM-D-glucose were included in the medium. The substitution of D-fructose or D-galactose for D-glucose resulted in very poor penetration rates (0-4%), but D-mannose was effective for fertilization (59-99% penetration). Incubations for sperm capacitation and egg fertilization in different media containing the various hexoses showed that rat epididymal spermatozoa could be partly capacitated without hexose, that D-glucose, D-mannose or D-galactose but not D-fructose is effective for sperm capacitation and that only D-glucose and D-mannose supported penetration of eggs in vitro.
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PMID:Effect of various hexoses on sperm capacitation and penetration of rat eggs in vitro. 69 Sep 72

Spermatozoa do not achieve full maturation and fertilizing capacity until passage through the epididymis. During this time they also gain motility, although spermatozoa do not move until after ejaculation. The organic fraction of human seminal plasma contains phosphate esters, particularly glycerylphosphorylcholine (GPC), phosphorylcholine (PCh), and inorganic phosphate (Pi). GPC is found in relatively high concentrations in the semen of many male animals, including man. GPC is synthesized by the epithelial cells of the epididymis, apparently under androgenic control. Consequently, it has been suggested that GPC might be a useful indicator of epididymal function. We have measured GPC, Pi, and PCh in fresh and frozen semen samples, using phosphorus nuclear magnetic resonance (31P NMR). All samples were assayed for phosphate esters. It was found that PCh was totally hydrolized to Pi. The average ratio of GPC to total phosphate (TP = GPC + Pi) remained constant at a value of about 0.1 for sperm counts over 20 million/ml. The ratio for azoospermic specimens was 0.02 or less; the same results were obtained from vasectomy specimens. This finding indicates that most of the GPC comes from the epididymis. There was a significant correlation between motility, progression, and the GPC ratio. Poor motility and progression in the specimens were accompanied by low GPC ratios regardless of the sperm counts.
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PMID:The role of phosphate esters in male fertility. 71 Jun 5

The testicular and epididymal sperm reserves of 32 adult crossbred European boars (mean age 17.4 months, range 15--21 months) raised and maintained in Ibadan, Nigeria were 43.77 x 10(9) and 207.20 x 10(9) cells respectively, and were correlated (P less than 0.01) with age and organ weight. The distribution of spermatozoa in the epididymis was 16, 6 and 78% in the caput, corpus and cauda epididymidis respectively. The testicular and epididymal sperm reserves were correlated (P less than 0.05), suggesting that sperm production and storage are associated. All the values studied were comparable with those reported for boars kept in temperate climates.
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PMID:Testicular and epididymal sperm reserves of crossbred European boars raised and maintained in the humid tropics. 72 73

1. Enzyme activities (units/g wet wt.) were determined in the caput and cauda epididymidis and in epididymal spermatozoa of the rat. 2. The activity of most enzymes in the cauda was between 50 and 100% of that in the caput, except that ATP citrate lyase was barely detectable in the cauda. 3. Spermatozoa, unlike epididymal tissue, contained sorbitol dehydrogenase but lacked ATP citrate lyase. NADP+-malate dehydrogenase, mitochondrial glycerol 3-phosphate dehydrogenase, succinate dehydrogenase, carnitine acetyltransferase and citrate synthase were 5 to 400 times as active in spermatozoa as in epididymal tissue. 4. 2-Oxoglutarate dehydrogenase was the least active member of the tricarboxylic acid cycle in all tissues and most closely matched the measured flux through the cycle. 5. The concentrations of hydroxyacyl-CoA dehydrogenase and carnitine palmitoyltransferase were equivalent to the more active enzymes of the tricarboxylic acid cycle, indicating the capacity for extensive lipid oxidation, and the presence of 3-hydroxybutyrate dehydrogenase suggests that these tissues can also oxidize ketone bodies. 6. Transfer of reducing equivalents from cytoplasm to mitochondrion is unlikely to occur by means of the glycerol phosphate cycle because mitochondrial glycerol 3-phosphate dehydrogenase is relatively inactive in epididymal tissue, whereas the cytoplasmic enzyme has little activity in spermatozoa, but transfer may be accomplished by the malate-aspartate shuttle. 7. Transfer of acetyl units from mitochondrion to cytoplasm could be effected by the pyruvate-malate cycle in the caput of androgen-maintained rats, but not in the other tissues because of the low activity of ATP citrate lyase. Acetyl unit transfer could take place via acetylcarnitine, mediated by carnitine acetyltransferase. 8. Castration resulted in a decrease in the concentration of nearly all enzymes, although subsequent administration of testosterone restored concentrations to values similar to those in animals maintained by endogenous androgen. The extent to which enzyme concentration was changed by an alteration in androgen status was highly variable, but was most marked in the case of pyruvate carboxylase.
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PMID:Activity and androgenic control of enzymes associated with the tricarboxylic acid cycle, lipid oxidation and mitochondrial shuttles in the epididymis and epididymal spermatozoa of the rat. 72 83

Marked variations in the 3beta-hydroxysterol content of hamster spermatozoa were observed as they progress through the epididymis. Cholesterol is the major sterol of caputal spermatozoa while the concentration of precursors of cholesterol was higher than that of cholesterol in caudal spermatozoa. One of these precursors has been identified as desmosterol. A second sterol has now been identified as 5alpha-cholestra-7,24-dien-3beta-ol by GLC-MS and by NMR. Its concentration is approximately 3-fold higher than that of cholesterol. This 3beta-hydroxysterol is also found in epididymal tissue.
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PMID:5alpha-Cholesta-7,24-dien-3beta-ol as a major sterol of the male hamster reproductive tract. 73 99

The effects of a number of prostaglandins on the metabolism of fructose by epididymal and ejaculated ram spermatozoa were investigated using conventional Warburg techniques. Spermatozoa from the two sources were collected concurrently during electrical stimulation; the epididymal spermatozoa were harvested via a cannula inserted chronically into one vas deferens and thus were free from exposure to the seminal prostaglandins. In general, the metabolism of fructose by the spermatozoa was little affected by a wide range of prostaglandins at a concentration of 20 micrograms/ml. Of the PGs present in semen, PGE2, PGE3 and PGF2alpha had no significant effects whereas PGE1 and PGF1alpha significantly increased lactate accumulation and the latter increased oxygen uptake, in both cases without significantly changing fructose utilization, fructose oxidized or CO2 production. Both 15-methyl-substituted PGE2 and PGF2alpha and their corresponding methyl esters failed to change fructose metabolism and it is unlikely therefore that the lack of response to PGE2 and PGF2alpha was due to their being metabolized by the spermatozoa during the incubation. Of a number of breakdown products tested, PGA1 and to a lesser extent PGA2 appeared to inhibit the Krebs tricarbocyclic acid cycle and 15-keto 13,14-dihydro-PGF2alpha appeared to stimulate it. In general, epididymal spermatozoa responded to the PGs in the same way as ejaculated spermatozoa. Thus we did not confirm a suggestion in the literature that spermatozoa have lowered sensitivity to PGs in vitro once they have been in contact with the PGs in seminal plasma.
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PMID:Effect of various prostaglandins on the metabolism of fructose by epididymal and ejaculated ram spermatozoa in vitro. 73 77


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