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)

Levels of glucose-6-phosphate cyclase (myoinsitol-1-phosphate synthase, EC 5.5.1.4) and myoinositol-1-phosphate phosphatase (myoinositol-1-phosphatase, EC 3.1.3.25) were determined in extracts of testes from10-, 20-, and 30-day-old rats, and in extracts of Sertoli cells, germinal cells, and epididymides. The specific activity of the cyclase was approximately 1/10th that of the phosphatase in all extracts found to contain either enzyme. Among cells in the testis examined, Sertoli cells had highest levels of enzymes required for inositol biosynthesis from glucose, while spermatocytes and round spermatids did not have detectable activity. Spermatozoa from the epididymis also had no detectable cyclase or phosphatase activity. In contrast, extracts of washed epididymides contained exceedingly high specific activities of these enzymes. Primary cultures of Sertoli cells, maintained in a chemically defined medium without added inositol, released inositol into the medium during three successive 24-h periods. The amounts released were greater in cells stimulated by dibutyryl cyclic AMP. Results were interpreted to indicate that inositol in the fluid of seminiferous tubules most probably originates from Sertoli cells, which synthesize inositol from glucose. Additional inositol in the fluid of epididymal tubules could readily be provided by metabolism of glucose by epididymal epithelial cells
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PMID:Myoinositol biosynthesis by Sertoli cells, and levels of myoinositol biosynthetic enzymes in testis and epididymis. 22 90

The de novo pyrimidine synthetic enzyme, aspartate carbamyltransferase, and the two pyrimidine salvage enzymes, uridine and thymidine kinases, of the rat testis and epididymis were measured 1, 2, 4, 6, 8, and 10 wk following unilateral vasectomy. Vasectomy had no effect on organ wet weights and on testicular and epididymal asparate carbamyltransferase and thymidine kinase activities. Increases in the uridine kinase activity of the caput epididymidis at 2 wk and of the cauda epididymidis from the second to the sixth weeks were the only significant enzymatic changes observed.
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PMID:Pyrimidine synthetic enzymes of the rat testis and epididymis following unilateral vasectomy. 22 15

Progesterone, epitestosterone (4-androstene-17 alpha-ol-3-one, EpiT) and 4- androstene-3-one-17 beta-carboxylic acid (COOH), three known in vitro inhibitors of 5 alpha reductase, were injected daily for 30 days to male rats to study their effect on some parameters of epididymal function. Progesterone at the dose of 750 and 2000 micrograms/day decreased fertility by 59% and 50% respectively. EpiT at a dose of 1500 micrograms/day decreased fertility by 74%. These treatments did not change the sperm counts in the cauda epididymis. Treatment with COOH did not decrease fertility. Progesterone at 750 and 2000 micrograms/day and EpiT at 750 micrograms/day decreased the weight of the epididymis, prostate and seminal vesicles. None of the compounds tested produced variations in body weight or in the weight of liver and testis. The 5 alpha reductase activity of epididymis, testis and liver was diminished by progesterone treatment, while EpiT decreased only that of testis and liver.
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PMID:Effect of in vivo administration of 5 alpha reductase inhibitors on epididymal function. 26 19

Two siblings with 46,XY male pseudohermapthroditism were demonstrated to have the phenotype characteristic of 5 alpha-reductase deficiency, namely normal testes and male Wolffian duct derivatives (epididymis, vas deferens, and seminal vesicle) terminating in a blind-ending vagina. Clitoromegaly was present at birth and increased further at the time of expected puberty. The diagnosis of 5 alpha-reductase deficiency was confirmed by demonstration of male levels of testosterone and testosterone precursors before and after hCG administration, elevated plasma testosterone to dihydrotestosterone and urinary etiocholanolone to androsterone ratios, and by in vitro studies indicating 5 alpha-reductase enzyme deficiency in the epididymis of one patient. Studies of control and mutant epididymal microsomes indicated that a single enzyme is responsible in the normal person for the 5 alpha-reduction of testosterone and cortisol (and probably other delta 4-3-ketosteroids as well) and that 5 alpha-reductase activity is undetectable for all substrates examined in the mutant. This finding explains why the formation of 5 alpha-reduced glucocorticoids is also defective in the disorder.
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PMID:Clinical, endocrinological, and enzymatic characterization of two patients with 5 alpha-reductase deficiency: evidence that a single enzyme is responsible for the 5 alpha-reduction of cortisol and testosterone. 26 18

The resolving capacity of magnification testicular angiography, as related to the known vascular anatomy of the testis and epididymis, was analysed on the basis of 9 normal angiographies and 8 cases of hydrocele with proven normal status of the testis and epididymis. The intratesticular vascular arrangement was demonstrated remarkably well, but of the epididymal vascularity only that in the head of the epididymis. The vascular anatomy of the testis as resolved by angiography may be utilized in the diagnosis of the location and nature of intra- and extratesticular mass lesions.
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PMID:Angiography of the testicular artery. III. Testis and epididymis analysed with a magnification technique. 34 7

The structural and functional integrity of the epididymis, the acquisition of fertilizing ability by spermatozoa and their viability within the epididymis are androgen dependent phenomena. Although the precise mechanism by which sperm maturation and viability in the epididymis are brought about by androgen are not clearly understood, it is generally held that specific epididymal secretions produced under the influence of androgen affect these events. Though the spermatozoa appear to remain viable in a low androgen environment, sperm maturation requires a relatively high androgen environment. Against this background the potentiality of antiandrogens as extragonadal antifertility agents has been discussed. Studies with steroidal and nonsteroidal antiandrogens have revealed that in adult animals the secretory activity of the epididymis, as evidenced by the level of glycerylphosphorylcholine, either remains unaffected or is stimulated under their influence. These studies have further indicated that the extragonadal antifertility action of antiandrogens will depend upon their ability to (1) lower the testicular androgen synthesis and/or androgen binding protein, which possibly serves as a carrier of androgen from the testis to epididymis; (2) to lower local androgen synthesis as a result of reduced levels of circulating androgen, and (3) to inhibit 5 alpha-reduction of testosterone to dihydrotestosterone and/or to inhibit androgen binding to receptors. Success in the rational development of new antifertility agents for male which will act by controlling epididymal function will depend upon a clear understanding of the factors that regulate epididymal secretion and the role of epididymal secretions in sperm maturation and survival.
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PMID:Regulation of epididymal function and sperm maturation--endocrine approach to fertility control in male. 38 17

The effects of castration and testosterone replacement therapy on the histology and biochemical composition (RNA, DNA, total protein, alkaline phosphatase, acid phosphatase, hyaluronidase, sialic acid, glycogen, phospholipids, and glycerylphosphorylcholine [GPC]) of the epididymis of the rabbit and rhesus monkey were investigated. Castration produced marked ponderal, histologic, and biochemical changes in the epididymis. In the androgen-deficient state the tubular diameter and epithelial cell height were reduced and there was an increase in interbular stroma. The levels of RNA, DNA, phospholipids, and GPC were also reduced in castrated animals. Testosterone treatment restored the histologic features and the levels of various biochemical constituents to a great extent but not to the intact control level. The importance of endocrine and exocrine factors of the testis in relation to epididymal function is discussed.
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PMID:Androgenic control of epididymal function in rhesus monkey and rabbit. 40 58

By ligation of the efferent duct and the corpus epididymis, the GPC concentration in this delimited anterior region decreased. However, HCG infection increased the GPC concentration. When spermatozoa are present in the epididymal tubule there is always a decrease in GPC concentration in these experimental conditions. Activity of the epididymis is disturbed by ligation.
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PMID:[Influence of testicular fluid, spermatozoa and androgens on physiological activity of rat epididymis]. 40 49

A specific androgen binding protein has been demonstrated in the seminal plasma of adult Ram. This protein binds especially to 5 alpha-DHT and testosterone and much lower to oestradiol-17 beta. Its characteristics such as Ka (in order 10(9) M(-1) at 4 degrees C), relative mobility (Rf) and its specificity are similar to those of the androgen binding protein (ABP) of the Rete Testis Fluid and the epididymal plasma of the Ram. It is probable that this protein secreted from the testis, crosses the epididymis before being secreted in the seminal plasma at the moment of the ejaculation.
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PMID:[Demonstration of a specific androgen binding protein (ABP) in the seminal plasma of the ram]. 41 95

Rat spermatozoa are highly dependent on the milieu of the normal epididymis for their maturation and survival, and die within a few days after androgenic support of the epididymal epithelium is withdrawn. The immediate changes in the ultrastructural organization of the epithelial cells of the rat epididymis, 2, 4, 6 and 14 days following castration have been monitored by morphometric analysis of localized regions of the caput and cauda epididymidis. While castration results in greater endocytosis by principal cells (Moore and Bedford, '79), many of their early structural changes following androgen withdrawal (disappearance of vesicles from the cell apex, reduction in rough endoplasmic reticulum, a drop in the volume of the Golgi cisternae and increase in lysosome content) seem indicative of inhibition of a secretory function. By contrast with the regressive response of the principal cell, the ultrastructure of clear cells in the cauda and of apical cells in the caput region appeared unchanged up to 14 days after castration. The implications of this evidence for specialized functions, and the suggestion of a differential androgen dependence among major cell types of the epididymal epithelium, are discussed briefly.
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PMID:Short-term effects of androgen withdrawal on the structure of different epithelial cells in the rat epididymis. 42


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