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)

Daily feeding of 1 mg of alpha-chlorohydrin per kg body weight to boars prevented fertility completely when the ejaculate was used for insemination. The semen charactreated than in untreated boars, but the sperm morphology was otherwise normal. In vitro addition of 5 mg/epididymal contents from the treated boars revealed normal Na+, K+ and glycerylphosphorylcholine concentrations. The movement of sperm cytoplasmic droplets was completed on all spermatozoa more distally in treated than in untreated boars, but the sperm morphology was otherwise normal. In vitro addition of 5 mg/100 ml of alpha-chlorohydrin to ejaculate boar semen completely inhibited and 2.5 mg/100 ml decreased fertility. Removal of the alpha-chlorohydrin prior to insemination partially restored fertility. 14C-alpha-chlorohydrin was shown to be more firmly bound to boar spermatozoa than 14C-carboxyinulin and could not be removed from the spermatozoa with 3 washings. The contraceptive mechanism of the drug is suggested to be alkylation of the sperm membrane by free alpha-chlorohydrin in the epididymis.
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PMID:Effect of low doses of alpha-chlorohydrin on fertility and semen characteristics and binding of the drug of spermatozoa in swine. 0 83

Vitamin A concentration was fluorometrically measured in epididymal and ejaculated rabbit spermatozoa and in some of the sperm cells subcellular components. The concentration of vitamin A in the epididymal cells was about one-half that observed in the ejaculated spermatozoa (2.68 as against 1.05 mug/10(8) cells) and seemed to be the same in the sperms obtained from both the head and the tail of the epididymus. The concentration of vitamin A was also found to be significantly higher in the seminal plasma than in the epididymal secretion (0.06 as against 0.039 mug/mg protein respectively). Practically all the vitamin A was found in the fractions obtained by treatment with hypotonic MgCl2 (acrosomal region) and/or with hyamine and dithiothreitol (plasma membrane). It was concluded that the sudden increase in the sperm concentration of vitamin A that occurs upon ejaculation may be required for the stabilization of the acrosomal and plasma membranes.
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PMID:Participation of vitamin A in the maturation of rabbit spermatozoa. 0 95

The in vivo and in vitro effects of cyproterone acetate (CA), an antiandrogenic compound, on the proteinase activities in epididymal and testicular spermatozoa in male albino rats was studied. CA was injected intramuscularly at a dose of 50 mg/kg daily for 10, 20, and 30 days. The testis and epididymis were homogenized and submitted for enzyme assay. The in vitro experments involved the incubation of supernatents from centrifuged testis and epididymis for 30 minutes with CA. Proteinases were assayed using acid-denatured hemoglobin as substrate. Acid proteinase activities increased in both testis and epididymis, but the inhibition of neutral and alkaline proteinase activities was greater in epididymis than testis with both long- and short-term treatment with CA. It is suggested that CA inhibits the maturational processes in the epididymis rather than spermatogenesis in the testis.
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PMID:Effect of cyproterone acetate on the proteinase activities of adult rat testis and epididymis. 1 62

Epididymal spermatozoa from bull, rabbit and ram were incubated in homologous epididymal plasma or seminal plasma in a buffered saline-based medium with or without serum albumin. The spermatozoa were either diluted directly into the medium or were washed first. No effect of washing was observed on the subsequent reaction of the cells to the different media. A considerable proportion of the populations of epididymal spermatozoa survived (i.e. continued to exhibit motility) for up to 22 h at 30 degrees C in the simple saline-based medium. Initially epididymal plasma had a slight stimulatory effect on sperm motility in ram and bull but it had no effect on sperm survival in any of the 3 species. Seminal plasma stimulated motility markedly in ram initially, but in all 3 species seminal plasma was detrimental to survival: in ram even a 15-min exposure to the fluid reduced survival. Serum albumin also stimulated motility; it delayed, but did not prevent, the detrimental effect of seminal plasma, although it had no effect itself on survival. The effects of epididymal plasma, seminal plasma and serum albumin on surface properties of epididymal spermatozoa, i.e. agglutination, sticking-to-glass and eosinophilia, were also noted. These varied between species and there was no correlation between these effects and the effects on motility and survival.
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PMID:The maintenance of motility and the surface properties of epididymal spermatozoa from bull, rabbit and ram in homologous seminal and epididymal plasma. 3 36

Spermatozoa were collected from the caput and cauda epididymidis of rabbits and rats and diluted in Hank's solution containing BSA, with various concentrations of Na+ and K+. Ionic strength and osmolarity were kept constant. Motility was assessed at various intervals during incubation at 25 degrees C. In the pH range 7.05--7.20, the motility of rabbit spermatozoa was not affected by changes in the ratio of K+ to Na+. Similarly, the motility of rat cauda spermatozoa was not altered, but that of caput spermatozoa was slightly depressed by a high K+/Na+ ratio. In the pH range 5.45--5.85, rabbit cauda and caput spermatozoa had much greater motility in media with a high K+/Na+ ratio. The reverse result was obtained for the rat. These findings indicate that the motility of epididymal spermatozoa is influenced by external Na+ and K+ concentrations and that this phenomenon is pH-dependent.
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PMID:Effect of sodium and potassium concentrations and pH on the maintenance of motility of rabbit and rat epididymal spermatozoa. 4 45

After separation of three epididymal acid phosphatases their biochemical properties were differently studied. With appropriate substrate and inhibitor selection the distribution of the enzymes in different segments as well as the subcellular fractions of the rat epididymis was also demonstrated. The same biochemical differences were also utilized in the histochemical localization of the enzymes. It was found that Enzyme I had a pH-optimum at 5.0, a molecular weight of 97 000 and Km-constant of 0.901 mM. It was highly sensitive to tartrate and fluoride and it was localized in lysosomes as well as in the epididymal spermatozoa. Enzyme II had an optimum at pH 5.7, a molecular weight of 67 000 and Km-constant of 0.806 mM. It was also inhibited by fluoride but more resistant to tartrate. Its subcellular site was also particulate, but it was also found in the epididymal fluid. Enzyme III had an optimum at pH 5.2, a molecular weight of 135 000 and Km-constant of 0.685 m. It was resistant to low concentrations of fluoride and tartrate but sensitive to heavy metal ions. The enzyme was soluble and it behaved incoherently in thermal inactivation. All enzymes revealed the highest activity in the thin middle segments of the epididymis. Histochemical naphthol substrates gave a diffuse reaction in the epididymal epithelial cells. With the lead salt methods glycerophosphates and p-nitrophenylphosphate gave somewhat different results depending on their specificity as substrates for the epididymal enzymes. Both substrates gave a strong reaction supranuclearly in the Golgi area of the chief cells. This activity was inhibited by tartrate and was most probably due to Enzyme I. The epididymal corpus and cauda showed additionally a very strong apical activity in the chief cells with p-nitrophenylphosphate. This activity was resitant to tartrate but sensitive to fluoride. It was concluded that this enzyme represents Enzyme II activity. Similar activity was also found in the dissolving "holocrine" cells of the corpus and the cauda. The activity of the soluble Enzyme III could not be revealed with the present methods and the spermatozoa in the tubular lumina remained unstained.
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PMID:Acid phosphatases of the rat epididymis. II. Biochemical characteristics, subcellular distribution and histochemical localization. 7 Jan 77

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

Average lactate dehydrogenase (LDH) isoenzyme patterns the content of H subunits, total LDH activity, total malate dehydrogenase (MDH) activity and the m- MDH/s-MDH ratio were determined in twelve muscles and the male genital tract of the rabbit. LDH(1) was the predominant form in the heart, soleus and masseter muscles, LDH(3) in the lingual muscles and LDH(5) in the other muscles analysed. In the muscles, an increase in the percentual proportion of M subunits was accompanied, by a proportional increase in total LDH activity and a decrease in total MDH activity, especially m-MDH. LDH isoenzyme patterns and LDH and MDH activities are useful for obtaining some idea about the proportion of individual muscle fibres. Activity accounted for by H subunits was roughly the same in all the muscles analysed, indicating that the synthesis of H subunits is independent of the type of muscle fibre and of the oxygen supply of the muscular tissue, and also that isoenzymes composed chiefly of H subunits are not localized preferentially in the mitochondria. Similar relationships between LDH isoenzymes and LDH and MDH activities were found in the testicular and epididymal tissues. The tests and the head of the epididymis mainly contain LDH isoenzymes composed of H subunits. The total LDH activity in these tissues is relatively low and their MDH activity is relatively high compared with the body and tail of the epididymis. The proportion of H subunits in the ampulla, the seminal vesicles, the coagulating glands and the prostate is also high. Cowper's glands have a high LDH(5) and LDH(4) concentration. One of two LDHx isoenzymes were found in the testes and spermatozoa.
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PMID:Lactate and malate dehydrogenases in the muscles and male genital tract of the rabbit. 13

Three different autoantigens (S, P and T), extracted and separated from guinea-pig spermatozoa, give rise to an autoimmune aspermogenic orchitis (AIAO) when injected with Freund's complete adjuvant (FCA). They also induce specific antibodies, such as anaphylactic (with S and P), complement-fixing (with P and T), spermotoxic (only with T) and precipitating and Arthus-inducing antibodies (only with P). Passive transfer of AIAO was attempted by injections of high total doses (15-20 ml per animal) of immune sera directed against one of the three antigens. Successful passive transfers were evaluated by the intensity of the epididymal and testicular lesions which were comparable to the actively induced ones, and by the rapid appearance of these lesions in less than 1 week and their lasting for at least 2 weeks. The disease was passively transferred with anti-P immune sera in as many as 64% of these cases and up to 40% with anti-T immune sera. Anti-S sera did not transfer AIAO more than did control normal and anti-DNP-BGG guinea-pig sera. The incidence and intensity of lesions were greatly for anti-P or slightly for anti-T increased by pretreating the future recipients with FCA. Hyperimmune sera are considerably more effective than early sera even when the latter are used in a time sequence reproducing that of the active reaction. The orchitogenic acitvity of anti-T sera appears to be localized in IgG2 DEAE fractions while that of anti-P has been found only in Ig1-containing DEAE fractions.
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PMID:Passive transfer of autoimmune aspermogenic orchiepididymitis (AIAO) by antispermatozoa sera. Influence of the type of autoantigen and of the class of antibody. 13 89

Daily injection in the rabbit of 60 mg cyclophosphamide, during four days, product during 8 to 9 weeks one importance decrease of the number and the mobility of the ejaculated spermatozoa. This interval correspond with the spermatogenesis and epididymal transit period. Low doses injections product only one mobility decrease.
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PMID:[Effect of short-term cyclophosphamide administration on rabbit sperm]. 14 Jul 51


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