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)

Testicular and accessory sex gland function was examined in 20 mature breeding rams that received graded dosages of testosterone (T) by subdermal Silastic implants or intramuscular injections. Treatments were imposed for 72 days during the normal breeding season. As compared with control rams rams implanted with 20 T-filled Silastic capsules had greatly reduced testes (24%) and epididymides (53%) weights as well as total daily sperm production (3.3%) and epididymal sperm reserves (3.9%). These effects were produced when serum T concentrations were increased four-fold over those of control rams, serum LH was nondetectable and serum FSH was substantially decreased. Testicular weight and total daily sperm production were less dramatically reduced in rams given T (2 x 250 mg/day) by injection. In spite of the high serum T concentrations observed in injected rams, weights of the accessory sex glands were not significantly affected. Treatment with 5 or 20 T-filled Silastic capsules or by injection of T not only suppressed gonadotropin secretion and spermatogenesis but also reduced T concentrations in rete testis fluid. A high correlation (r = 0.94, P < 0.01) between daily sperm production and T concentrations in rete testis fluid was calculated in this study. Results presented herein indicate that 1) treatment of rams with exogenous T affects spermatogenesis in a dose-dependent manner and 2) spermatogenic yield is related to T concentrations in fluid of the rete testis.
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PMID:Dose-dependent inhibition of spermatogenesis in mature rams with exogenous testosterone. 677 11

A protocol for the assessment of oligozoospermia prior to AIH is presented. Three to six carefully performed semen analyses at optimal intervals are required to confirm oligozoospermia. Routine semen analysis consist of volume, pH, viscosity, sperm count, motility, morphology, agglutination, fructose content, and leukocytes. Because of the high incidence of reproductive tract infection and chromosomal abnormalities in oligozoospermic men, microbiological investigation and full chromosomal analyses should be performed in all cases with sperm counts below 10 million/ml. Chromosomal abnormalities are an indication to reject a couple from AIH. Genital tract infections must be treated prior to insemination. Only sperm counts below 10 million/ml require the estimation of FSH levels. The existence of an oligozoospermia group with pituitary adenoma justifies routine PRL measurements in all cases of oligozoospermia and further investigations such as visual field examination and sella tomogram in case of hyperprolactinemia. Testicular biopsy may indicate an epididymal block that can be surgically repaired. Simultaneous in-depth evaluation of the female partner is emphasized, as oligozoospermia in the man does not rule out the possibility of an additional infertility factor in his partner. It is still controversial whether or not AIH, as compared to intercourse, will improve the conception rate for oligozoospermic men.
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PMID:Andrological evaluation of oligozoospermic men for AIH. 678 5

A specific antiserum to ovine follicle stimulating hormone (AS/FSH) raised in rabbits and administered to prepubertal mice from days 5 to 35 of age, inhibited intermediate and type B spermatogonia. Development of spermatocytes, spermatids, and spermatozoa was affected, indicating a role for FSH in the initiation of spermatogenesis. Decrease in the testicular and epididymal weights, but not that of seminal vesicles and ventral prostate, demonstrated the specific action of AS/FSH. Reduction in the weights of the epididymis in AS/FSH-injected mice accompanied by the absence of spermatozoa in the lumen suggests a possible role for FSH in spermiation.
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PMID:Effect of FSH deprivation on spermatogenesis in prepubertal mice. 681 Jul 74

ABP is a protein found in the testicular cytosol or secreted by Sertoli cells in the rete testis fluid. It has a high affinity for androgers and binds specifically 5 alpha-DHT and testosterone (but to a lesser extent). The binding capacity is saturable. ABP is measured by steady state polyacrylamide gel electrophoresis or by separation on dextran coated charcoal. ABP moves from testis to epididymis where its binding activity is totally or partially destroyed from caput to cauda epididymis. In some species (ram, bull, billy goat) but not in others (human, boar, stallion) ABP is present in the seminal plasma of the ejaculate. In some species like the rat, ABP is also secreted in the testicular blood stream by Sertoli cells through the basement membrane of the seminiferous tubules. ABP varies with age and with season. Its production is under separate endocrine control of FSH and testosterone and its transport from testis to epididymis is specifically controlled by FSH. Through its binding activity, ABP may play a role in spermatogenesis and epididymal sperm maturation by enhancing the local concentration of androgens around the germinal cells and the male gametes. However ABP is not present in some species, like the pig, although their spermatogenesis and epididymal sperm maturation are normal.
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PMID:[ABP: the testicular protein that binds androgens]. 681 32

The effects of gonadotropins and gonadal steroids on androgen-binding protein (ABP) production and its distribution among the epididymis, seminiferous tubule fluid (STF), testicular interstitial fluid (TIF), and blood were studied in 300-g adult male Sprague-Dawley rats. The rats either received no treatment or their pituitary function was suppressed by administration of the GnRH antagonist [AcD2Nal,D4ClDPhe2,D3Pal3,Arg5,DGlu6 (AA),D-Ala10]LHRH (antagonist). Other groups of rats were treated with hCG, FSH, FSH plus hCG, testosterone, or estradiol, alone or together with antagonist. Treatment was conducted for 30 days, after which time, ABP was detected by its ability to bind [3H]5 alpha-dihydrotestosterone. Transport of ABP from the testis to the epididymis was inhibited by antagonist administration. Simultaneous treatment with antagonist and hCG, or antagonist and hCG plus FSH prevented antagonist-induced inhibition of ABP transport. Neither FSH, testosterone, nor estradiol alone was effective in this process. Inhibition of ABP transport to the epididymis was accompanied by its accumulation within the testis. Treatment with antagonist and FSH resulted in a 4.5-fold increase in the concentration of ABP in TIF, but had little effect on the amount of ABP in STF, indicating selective secretion of ABP from the basal surface of the Sertoli cells. Treatment with antagonist alone, antagonist together with testosterone or estradiol, or estradiol alone resulted in increased concentrations of ABP in both TIF and STF, but the increase in TIF was proportionately greater. Treatment with hCG or FSH plus hCG alone or with antagonist not only facilitated ABP transport to the epididymis, but also increased TIF levels of ABP above control values. The former treatment resulted in increased concentrations of testosterone in TIF, but not in STF. Both treatments resulted in testosterone levels in both compartments that were higher than those in animals treated with antagonist alone. No treatment had a statistically significant effect on blood levels of ABP. About 50% of ABP synthesis appears to be constitutive, i.e. is not regulated by hormones. Although ABP production continues in the presence of antagonist, its transport to the epididymis is halted, indicating that epididymal transport of ABP is a hormone-dependent process. It is likely that elevated intratesticular levels of testosterone or FSH and testosterone acting in concert regulate epididymal transport of ABP.
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PMID:The effects of a gonadotropin-releasing hormone antagonist on androgen-binding protein distribution and other parameters in the adult male rat. 764 9

Azoospermia in two spermiograms, normal FSH and normal testicle size are sufficient for the diagnosis of excretory azoospermia and constitute an indication for surgery. Over the last 15 years, in 642 men an epididymo-vasostomy was performed for inflammatory (51%), inborn (44%) or acquired (5%) epididymal obstruction. In 327 selected cases permeability ranged between 11 to 76% according to the location of the anastomosis and fertility followed in 0-52%. Vaso-vasostomy was done in 724 men. Depending on the time after sterilisation or herniotomy obstruction, permeability ranged between 52% and 92%, fertility between 38% and 74%. Double-layered anastomosis with sealing of the anastomoses by fibrin glue improved the results. Special operations for vas mobilisation and testicle elevation which avoid tension upon the anastomosis are outlined. In four men with long obstructions of the vas, testicle transposition into the inguinal area was performed; three of them had a positive postoperative spermiogram and two of them fathered a child. With increasing duration of obstruction the quality of postoperative spermiograms decreases. Sperm autoantibodies were significantly elevated in only 3% of 531 men, and in most cases normal values were seen after relief of obstruction. Reasons of seminal anastomoses are: defective technique, sperm leak, traction upon the anastomosis, infection and epididymal damage. The frequency with which the operation is performed is the main determinant of the competence of the surgeon and the chances of success.
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PMID:[Seminal tract reconstruction: 15 years experience]. 787 75

This study was carried out on 25 patients with azoospermia and normal serum FSH levels signifying obstruction as its cause. To determine the site of obstruction semen transferrin levels, carnitine and fructose were estimated. Patients with an obstruction at the testis-epididymal junction had low levels of transferrin but normal levels of carnitine and fructose. Patients who had lower levels of transferrin and carnitine, but normal levels of fructose had obstruction at the epididymal level, probably in the tail of the epididymis. Obstruction of the ejaculatory ducts was signified by lower levels of all parameters in the semen. Our study showed that levels of transferrin, carnitine and fructose when used in conjunction with each other could localize the site of obstruction in azoospermia.
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PMID:Demonstration of the site of obstruction in azoospermia by biochemical markers. 808 7

Ninety-day-old Sprague-Dawley rats were intoxicated for 70 d with lead, given either as 0.3% lead acetate in drinking water or by inhalation as 5 mg m-3 lead oxide. Direct or transmitted lead toxicity for the male reproductive system was assessed in the rats and their offspring from pituitary and genital organ weights after exposure, the numbers of Sertoli and germ cells, the number, motility and morphology of epididymal spermatozoa, the levels of plasma testosterone, LH and FSH and fertility tests. Whole blood lead levels were similar after lead ingestion and after inhalation (58.0 +/- 1.7 micrograms dl-1 vs. 51.1 +/- 1.8 micrograms dl-1). Lead acetate ingestion did not affect the reproductive system or fertility of rats. Inhalation of lead oxide did not affect fertility either, but seminal vesicle weight dropped significantly, which might suggest an alteration in the pattern of testosterone secretion. In the male progeny of sires that inhaled lead, the number of epididymal spermatozoa decreased but this did not interfere with fertility. Our results show that for the doses studied, lead inhalation and lead ingestion do not produce strikingly different effects on the male rat's reproductive system. Differences between the present findings and those of others might be due to difference of rat strain or of age at exposure.
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PMID:Effect of ingestion and inhalation of lead on the reproductive system and fertility of adult male rats and their progeny. 809 17

Active immunization of adult rats with a GnRH fusion protein was used to inhibit gonadotropin secretion and to establish an in vivo model for studying the hormonal control of spermatogenesis. The model was characterized in terms of the efficacy of the immunogen as well as the time course and nature of the immunological and biological responses. To study the reinitiation of spermatogenesis, testosterone (T) was chosen for this initial study as it is known to restore spermatogenesis in gonadotropin-deficient rats. Adult Sprague-Dawley rats were actively immunized with a proprietory GnRH immunogen (BA-11, 100 micrograms s.c.) every 4 wk. After 12 wk, 58% of animals showed markedly suppressed testicular size, as assessed by scrotal palpation, and were classed as responders. Serum LH, FSH, and T as well as the testicular elongated spermatid count (ESC) and epididymal sperm were undetectable in responding animals. Marked reductions in testicular (29% of control), prostatic (8% of control), and epididymal (32% of control) weights were seen. Spermatogenesis was severely disrupted with no evidence of progression beyond round spermatids. To study the action of T in GnRH-immunized animals, T (defined by lengths of s.c. silastic implant, T3-T24 cm) was given to responding animals. Animals were killed 2, 8, and 12 wk after T24 administration. In response to T24, serum T levels increased to 4 times control levels, serum FSH levels were restored to 65% of control levels by 2 wk, and serum LH remained undetectable. Testicular weight increased to 80% of control levels at 12 wk (p < 0.05 vs. control). Epididymal and prostatic weights were normalized by T. ESC increased to 82% of control values at 12 wk (110 +/- 10 vs. control 134 +/- 8 million/testis, p = 0.001). Spermatogenesis was histologically normal after 8 wk of T24 treatment. To study the time course and dose response of T action, animals were immunized with another GnRH immunogen (BA-17), which yielded an 87% response rate at 12 wk. Testicular weight increased by Day 5 of T24 treatment, and a clear dose-response effect was apparent. The restoration of ESC was delayed compared to that of testicular weight (no restoration at 2 wk) and required > or = T6 treatment. Rats immunized for 20 wk and then given T24 treatment showed a similar pattern of restoration in testicular weight and ESC. Serum FSH was normalized by Day 2 of T treatment by doses > or = 3 cm.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Testosterone effects on spermatogenesis in the gonadotropin-releasing hormone-immunized rat. 814 46

The effect of flutamide (FLU) administered during 6 weeks at doses of 50 or 100 mg kg-1 body weight, on various reproductive characteristics of sexually active male golden hamsters was studied. The weight of seminal vesicles and epididymides showed a dose dependent inhibition with FLU, while testicular weight exhibited a biphasic response, its value being increased by 20% at lower FLU doses and reduced by 15% at higher FLU doses. An elevation of testicular and epididymal androgen-binding protein (ABP) content and also of testicular testosterone content was observed with both doses of FLU. Serum levels of LH and testosterone exhibited a four-fold increase, at both doses of FLU, while FSH serum level was elevated depending on the dose of FLU used. Results suggest that in the golden hamster the maintenance of the weight of testes and accessory organs depends mainly on androgenic stimulation, while production and transport of ABP is probably regulated by gonadotropins.
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PMID:Flutamide as a tool to study the hormonal regulation of the reproductive tract in the golden hamster. 818 57


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