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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of androgens on the male accessory glands of the rat was assessed in terms of changes in weight and of the specific activity of the mitochondrial enzymes, succinate dehydrogenase, glycerolphosphate dehydrogenase and pyruvate carboxylase, in the epididymis. In some instances, the activity of the cytoplasmic enzymes, hexokinase and phosphofructokinase, was also measured and the influence of androgens on these enzymes was found to be similar to that on the mitochondrial enzymes. After the administration of androgen to castrated rats the specific activity of enzymes reached a new steady state sooner than did epididymal weight. The time taken for the specific activity of the enzymes to reach a new steady state after the removal of androgen was variable, depending on the enzyme and the region of the epididymis. This time was generally longer, however, than the time taken for induction, and in the case of glycerolphosphate dehydrogenase, the decline of activity was slower in the cauda than in the caput. In castrated animals, about 100 times as much androgen was required to attain maximum tissue weight as was required to attain maximum enzyme activity. The epididymis, prostate and seminal vesicles responded similarly to androgen in terms of the dose-response pattern and the time taken for tissue weight to attain a new steady-state value, although the gain in weight of the epididymis relative to its weight in unstimulated control animals was less than the relative gain of the other accessory glands. Enzymes in the cauda epididymidis required lower amounts of androgen to elicit maximum activity than were required by those in the caput. The rate of change in the accessory glands in attaining new steady-state levels of tissue weight and enzyme activity was independent of the dose of androgen except during the first few days of hormone administration. Androgens were the most effective steroids in stimulating an increase of tissue weight and enzyme activity, although some changes were induced by oestradiol-3-benzoate and progesterone.
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PMID:Influence of androgens on the weights of the male accessory reproductive organs and on the activities of mitochondrial enzymes in the epididymis of the rat. 49 85

Since the synthesis and maturational processes of sperm are associated with characteristic alterations in different marker enzyme activities in testes and epididymis, it is possible to monitor these enzymes to investigate whether 3 antispermatogenic agents, WIN 18 446, alpha-chlorohydrin (AC), and cyproterone acetate (CA), have any characteristic effects on biochemical events associated with spermatogenesis and maturation of sperm; acid, neutral, and alkaline proteinases, particulate and soluble arylamidases, and sialidase were studied after treatment with 1 of the 3 agents in male albino rats (CIBA strain) by measuring these enzyme levels in rat testicular and epididymal tissues. After WIN treatment, sialidase activity as well as sialic acid content increased in the testis, whereas no such effect occurred in the epididymis at any dose. At low dose, AC (10 mg/kg/day for 7 days) and CA (50 mg/kg/day for 10 days) decreased the sialic acid content and the sialidase activity in the epididymis, whereas the sialic acid and sialidase activity in the testis remained unchanged. At higher dose levels, AC (25 mg) and CA (50 mg) both affected the tissues significantly, i.e., enhancing sialidase activity and lowering sialic acid content. Therefore, the effect of CA and AC is more prominent on the maturational phenomena than the testicular spermatogenesis. AC and CA deserve further investigation for use as a male contraceptive. The relationship between proteinase, sialidase, and arylamidase activities and different phases of spermatogenesis and maturation was established by these test results.
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PMID:Epididymal and testicular enzymes as monitors for assessment of male antifertility drugs. 49 33

Adult male rats were treated with prostaglandin E2 (100 microgram/100 g body wt) during 60 days. Neither morphological alterations in genital organs nor modification in epididymal contractility were observed. Nevertheless, a significant diminution of fertility was registered. This was recovered after 30 days following the cessation of treatment. Since sperm maturation occurs in the epididymis, it is postulated that the decrease of fertility in our experiments was due to an incomplete maturation of germinal cells, induced by a reduction in the time taken by spermatozoa in passing through the duct.
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PMID:Effect of chronic treatment with prostaglandin E2 on male rat fertility. 49 39

In exploring the evolution and adaptive significance of epididymal function, we have studied the male excurrent duct and spermatozoa of a monotreme mammal--the echidna. Sperm maturation in the echidna excurrent duct appears simpler than that in most therians examined. Furthermore, neither the duct nor the spermatozoa of the echidna display specific therian characteristics; they bear a much closer resemblance to those of non-passerine birds. The echidna spermatozoon is filiform, the sperm tail has no distinctive features, and the anterior seventh of the undulating nucleus is covered by a modest acrosome. Immediately behind this a restricted apposition between plasma membrane and nuclear envelope constitutes a post-acrosomal ring. This is evident also in some reptiles and marsupials, whereas in Eutheria such a membrane association appears as the posterior ring at the base of the sperm nucleus. Maturation of spermatozoa in the Wolffian duct of the echidna appears to be expressed only in a changing capacity for motility and in loss of the cytoplasmic droplet. Neither surface, structural nor acrosomal changes that characterize sperm maturation in therian mammals have been detected in maturing echidna spermatozoa. The echidna duct displays little of the regional complexity of the epithelium that typifies this duct in the Theria. Of five regions distinguishable on the basis of epithelial morphology, the first two appear to be counterparts of efferent ducts by virtue of a low columnar, partially ciliated epithelium. The tall pseudo-stratified Golgi-rich epithelium of the major portion of the duct broadly resembles that of the therian epididymis, but it displays only two structurally distinguishable regions, the more distal being the site of a dense luminal secretion. The foamy epithelial cells of the fifth and terminal region, characterized by a mass of supra-nuclear vesicles and rough ER, suggest a secretory function that may in some way contribute significantly to the ejaculate, for accessory glands are poorly developed in monotremes. The possibility is considered that the relative complexity of epididymal function and sperm structure in therian mammals could have been determined by evolutionary change in the milieu of the female tract, and/or in the character of the egg vestments that the fertilizing spermatozoon must penetrate.
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PMID:An evolutionary view of the male reproductive tract and sperm maturation in a monotreme mammal--the echidna, Tachyglossus aculeatus. 50 51

The flow rate and composition of boar rete testis fluid were similar to those in other species studied previously. The total phospholipid phosphorus and phospholipid fatty acid content of boar spermatozoa decreased during maturation in the epididymis but the level of phospholipid phosphorus was slightly higher in ejaculated spermatozoa than in epididymal spermatozoa. During passage of the spermatozoa from the testis to the cauda epididymidis, loss of the major saturated acids (palmitic, 16:0, and stearic, 18:0) was extensive but partly recovered in the ejaculated spermatozoa. The mass of docosapentaenoic (22:5) and docosahexaenoic (22:6) acids tended to decrease continuously during maturation but the percentage of 22:6 by weight of total phospholipid fatty acid reached a maximum in the epididymis. Ejaculated boar spermatozoa contained considerably more phospholipid and phospholipid fatty acid than did ejaculated bull or ram spermatozoa.
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PMID:Lipid changes in boar spermatozoa during epididymal maturation with some observations on the flow and composition of boar rete testis fluid. 51 1

Smooth muscle electrical activity was recorded with suction electrodes from the partly or completely uncoiled epididymal duct of the rat in vitro. The electrical activity of the cauda epididymidis consisted of one or few spikes followed by a plateau of 1-2 sec. The frequency of electrical activity declined from the thicker-walled initial segment of the thin-walled initial segment, was increased to the level seen in the initial segment in the thicker, major portion of the caput epididymidis, declined in the corpus and fell steeply in the cauda epididymidis towards the vas deferens. Electrical activity spread over long distances in the distal cauda and epididymal vas. Elsewhere in the epididymis activity remained synchronous only for a short period in short segments.
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PMID:Spontaneous electrical activity of the rat epididymis in vitro. 51 32

The secretion of proteins of different segments of the guinea pig epididymis was studied using micropuncture and radiochemical techniques. Tissue and fluid samples were taken 24-48 hr after intraperitoneal injections of 2 mCi of tritiated lysine. Macromolecular secretion was higher in the caput than in the corpus and cauda. Labelled spermatozoa were detected in smears taken from the caput epididymis 24 hr after injection. Few labelled spermatozoa were found in the corpus and none in the cauda. Since the capacity of epididymal sperm for fertilization is apparently achieved before spermatozoa reach the cauda, the protein synthesized in the epididymal caput and corpus would account for trigering sperm maturation.
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PMID:Macromolecular secretion into various segments of the guinea pig epididymis. 51 5

Male Wistar Strain rats of known fertility were given subcutaneous dosage of three drugs, alpha-chlorohydrin, amino-alpha-chlorohydrin, and busulphan alone or in combination for a period of thirty days. Males were housed overnight with females at various times during the treatment and ninety days after cessation of treatment. There were significant differences in levels of glycerylphosphorylcholine in the epididymides of two treatment groups as well as differences in numbers of spermatozoa recovered from the reproductive tracts of female rats mated with males from four treatment groups. Treatment had no effect on the weights of the testes or sex accessory organs or sialic acid levels in the epididymis, fructose levels in dorso-lateral prostate and coagulating gland, or citric acid levels in seminal vesicle and ventral prostate of the treated males when compared to controls. The antifertility activity was probably mediated by an effect on epididymal spermatozoa and thereby subsequent change in sperm transport within the female genital tract.
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PMID:Agonistic properties of low doses of antifertility compounds in male rats. 51 10

The effects of unilateral orchidectomy on the adult rat epidiymal testosterone metabolizing enzymes, delta 4-5 alpha-reductase and 3 alpha-hydroxysteroid dehydrogenase, are investigated. Five weeks following unilateral orchidectomy, it is found that the activity of 3 alpha-hydroxysteroid dehydrogenase per organ is not altered, whereas delta 4-5 alpha-reductase activity decreased by more than 80% on the side of the orchidectomy. Neither accessory sex tissue weights, ventral prostate and seminal vesicles, nor the concentration of circulating testosterone, luteinizing hormone, follicle-stimulating hormone, or prolactin is altered by unilateral orchidectomy. These data indicate that (1) epididymal 3 alpha-hydroxysteroid dehydrogenase activity can be maintained by circulating androgens and that (2) the major factor regulating delta 4-5 alpha-reductase activity is not a substance secreted by the testes into the peripheral circulation. It is suggested that a substance directly secreted into the epididymis by the testis regulates epididymal delta 4-5 alpha-reductase activity.
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PMID:Effects of unilateral orchidectomy on rat epididymal delta 4-5 alpha-reductase and 3 alpha-hydroxysteroid dehydrogenase. 51 41

Administration of testosterone, oestrogen, progesterone and prolactin for seven days affected the epididymal lipids markedly whereas seminal vesicular and prostatic lipids were less affected. The increase in total lipids of caput epididymis by testosterone, oestrogen and progesterone was due to an elevation in neutral and phospholipid contents. However, progesterone alone caused an increase in total lipids of the cauda epididymides while oestrogen and prolactin decreased the same. In seminal vesicle and prostate, testosterone elicited a significant rise in total lipids. However, an opposite trend was obvious by the other three hormones. Testosterone alone was effective in elevating the total lipids, phospholipid, cholesterol and glycerides in prostates. Prolactin does not affect the prostatic lipids markedly. The significance of the lipid changes are discussed in relation to various physiological activities of sex accessories.
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PMID:Influence of hormones on accessory sex glands in males. 52 Nov 21


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