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)

In the present study rats were dosed from weaning, through puberty and gestation, to Day 15 of lactation with methoxychlor at 25, 50, 100, or 200 mg/kg/day. Morphological landmarks of puberty were measured, including the ages at vaginal opening, first estrus, and first estrous cycle in females and at preputial separation in males. In the female, estrous cyclicity, fertility, litter size, number of implantation sites, organ weights, and ovarian and uterine histology were also measured. The viability of the offspring (F1) and their fertility were evaluated using a continuous breeding protocol. Males were necropsied after breeding, the reproductive organs were weighed, and the cauda epididymal sperm counts were determined. One testis was used for histopathology, while the other was used to quantify interstitial fluid (IF) content, IF testosterone concentration, and testicular sperm production. Testosterone and androgen-binding protein were measured in the caput epididymis, and sperm motility and morphology were evaluated from a caudal sample. The serum and pituitary were saved for hormonal determinations. Methoxychlor accelerated the age at vaginal opening and first estrus, and the vaginal smears were cornified. Growth was retarded at 100 and 200 mg/kg/day and fertility was reduced when the females were bred with untreated or similarly treated males. In the highest-dose group, the mated females went from constant estrus into pseudopregnancy following mating, but they had no implants. In males, methoxychlor treatment markedly reduced growth, seminal vesicle weight, cauda epididymal weight, caudal sperm content, and pituitary weight. Puberty was delayed in the two highest-dosage groups. Testicular sperm measures were much less affected than caudal measures. Testis weight and histology were slightly affected, and testicular sperm production, sperm morphology, and motility were unaffected. Endocrine function of the testes and pituitary was altered by methoxychlor administration. Leydig cell testosterone production, in response to human chorionic gonadotropin challenge, was reduced and pituitary levels of prolactin, thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH) were altered. In contrast, serum levels of prolactin, FSH, and luteinizing hormone were unaffected. Serum TSH was reduced by 50% of control at 100 and 200 mg/kg/day, while pituitary levels were increased. Gonadotropin-releasing hormone concentration in the mediobasal hypothalamus was also elevated. In spite of the many reproductive alterations, the fertility of treated males was not reduced when they were mated with untreated females.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:A dose-response analysis of methoxychlor-induced alterations of reproductive development and function in the rat. 292 22

The oestrogen mestranol (0, 0.01, 0.1 mg/kg body weight per day) and the progestins medroxyprogesterone-acetate and norethisterone (0, 2, 20 mg/kg body weight per day each) in sesame oil were intubated intragastrically daily during gestational days 14.5 through 19.5 to pregnant rats. Males were studied as 20.5-day-old foetuses and 4-month-old adults for serum testosterone and LH concentrations, in vitro testosterone synthesis, anogenital distance (foetuses only) and testes, seminal vesicle and ventral prostate weights. Administration of 0.1 mg mestranol decreased by 35 to 70% basal and LH-stimulated testosterone synthesis by both foetal and adult testes in vitro (P less than 0.01). Foetal body weights (P less than 0.05), but not anogenital distances, were significantly decreased. Testosterone content in adult sera was reduced significantly (P less than 0.05) to less than 50% of control. Testes, ventral prostate, seminal vesicle and epididymal weights were unaffected by treatment. Medroxyprogesterone acetate or norethisterone administration did not alter testes endocrine function in foetal or adult offspring. In a small number of rats, pregnant for 10.5, 14.5 or 18.5 days, [3H]ethinyloestradiol was intubated and foetal and placental tissue examined for appearance and content of radioactivity. Radioactivity was detected in 10.5, 14.5 and 18.5 days old placentas, and 14.5 and 18.5 days old foetal liver, gonads and external genitalia. With [3H]medroxyprogesterone acetate, radioactivity was localized in 14.5 day placenta and foetal tissues. Thin-layer chromatographic analysis showed most of the activity to migrate as authentic ethinyloestradiol or medroxyprogesterone acetate. These results demonstrate inhibition of testicular testosterone synthesis by mestranol, presumably by being transferred across the placenta and acting in the foetus.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of prenatal administration of mestranol and two progestins on testosterone synthesis and reproductive tract development in male rats. 295 83

Treatment with cadmium chloride (CdCl2) and cyproterone acetate (CA) depressed angiotensin converting enzyme (ACE) activity significantly in testes and epididymal regions of the adult rats compared to the corresponding untreated controls. Exogenous testosterone to CA-treated rats significantly increased the enzyme activity both in the testes and epididymis, the effect in the latter being very significant comparable to CA-treated and untreated controls. Testosterone failed to induce ACE activity in the testes and caput epididymis of 30 day-old immature rats, but the enzyme activity was detected in corpus and cauda epididymis. Our findings indicate that ACE activity in the testicular complex is possibly linked with androgen and is concerned with spermatogenesis and sperm maturation.
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PMID:Androgen dependence of testicular and epididymal angiotensin converting enzyme. 298 87

m-Dinitrobenzene (m-DNB)-induced testicular atrophy has been attributed to a direct effect upon the germinal epithelium. However, such degenerative changes in the germinal epithelium should induce shifts in the testicular hormonal milieu, which would in turn alter the hypothalamic-pituitary gonadal axis in general. This study evaluated the endocrine status of male rats (killed 3 hr, 24 hr, 1 week, and 2 weeks) following a single oral dose of m-DNB (32 mg m-DNB/kg). Serum and pituitary leuteinizing hormone, follicle-stimulating hormone (FSH), and protactin and hypothalamic gonadotropin-releasing hormone (GnRH) concentrations were determined. Testosterone and androgen-binding protein concentrations in serum, interstitial fluid, seminiferous tubule fluid, and caput epididymis were also determined. In vitro basal and hCG-stimulated testosterone release was determined in the decapsulated testis. Results of the present study indicate that pituitary hormone concentrations and hypothalamic GnRH were unaffected after a single oral dose of m-DNB. Serum FSH was elevated at 2 weeks. There was a transient decrease in serum testosterone at 24 hr, which returned to control values at 1 and 2 weeks. Interstitial fluid, seminiferous tubule fluid, and caput epididymal testosterone concentrations were increased at 1 and 2 weeks. Basal testosterone release in vitro was increased at 2 weeks, while hCG-stimulated testosterone release was increased at 1 and 2 weeks. Androgen-binding protein concentrations in serum and interstitial fluid were increased at 1 and 2 weeks. Androgen-binding protein was increased at 24 hr and 1 week in seminiferous tubule fluid, but returned to control concentrations by 2 weeks. However, the total tubular content of androgen-binding protein was dramatically decreased at 2 weeks. Androgen-binding protein in the caput epididymis was unaltered following m-DNB treatment. These data demonstrate that m-DNB exerts a direct effect on the testes and not through alterations in hypothalamic and pituitary control of gonadal function.
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PMID:Changes in testicular and serum hormone concentrations in the male rat following treatment with m-dinitrobenzene. 313 88

Continuous low-dose gamma-irradiation of mature rats induced a progressive degeneration of the germ cells. Blood FSH increased by 127, 176 and 214%, respectively, after 55, 70 and 85 days of treatment when compared to FSH levels in control rats (8.50 +/- 0.60 ng/ml); conversely, serum LH and testosterone levels were unchanged. The Sertoli cell function was affected by the treatment from 70 days on, as attested by androgen binding protein (ABP) and transferrin secretions which diminished 35-40%. Serum ABP levels were not altered, whatever the duration of irradiation, even though epididymal ABP contents (as well as concentrations) diminished 34-60% when compared to those of the controls. Moreover, in purified Leydig cells, LH-stimulated intracellular cAMP levels, which were decreased by seminiferous tubule medium (STM) from control rats, were enhanced in presence of STM from treated animals. Testosterone output was stimulated 9-fold in presence of oLH and further increased (46-76%) from stages XIV-V by STM prepared from control and irradiated rats, respectively. After 85 days the STM effects on both cAMP and testosterone syntheses were zero. These results demonstrate a probable alteration of Sertoli cell function after irradiation, but also a role of the germ cells in the regulation of the synthesis of ABP, transferrin and Sertoli cell paracrine factors.
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PMID:Effect of continuous low-dose gamma-irradiation on rat Sertoli cell function. 314 90

Both ejaculated semen and epididymal contents from an individual male contain sperm that differ in various physicochemical characteristics. An experiment is reported in which epididymides from rats 5-24 months old were subjected to density gradient centrifugation to separate gametes of different stages of maturity. The research was designed to examine typical changes in "profiles" of sperm maturity during the reproductive lifetime of rats. Also, testosterone complexed with cyclodextrin that mimics the episodic release of the endogenous hormone was used to supplement the decreased circulating titers of some of the old males. Results revealed clear ontogenetic patterns of gradually decreasing reproductive competence as measured by absolute numbers of sperm, circulating levels of testosterone, and various other physiological markers of fertility. Sperm profiles also revealed age-specific changes with a shift toward progressively more mature, perhaps senile, gametes that begins at middle age. Testosterone supplementation (400 micrograms/kg b.w./day for 30 days) failed to restore sperm numbers or other measures of physiology in the old males, but the steroid modified sperm profiles to approximate more closely the profiles characteristic of young adult males than either untreated middle-aged or old males. The data were interpreted as suggesting that epididymal sperm profiles clearly identify males of different ages, and that the aging epididymis retains its capacity to respond to manipulations that modify the endocrine milieu.
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PMID:Epididymal sperm profiles in young adult, middle-aged, and testosterone-supplemented old rats. 319 59

Protein synthesis and secretion were examined in vitro by incubating minced tissue with [35S]methionine. The incorporation of label into tissue plus medium was linear for the 5 h of incubation. The percentage of available label incorporated into protein increased with the weight of tissue used. Approximately 13% of the label incorporated appeared in the medium after 5 h of incubation. Release of radioactive protein into the medium was characterized by an initial slow release (1-2 h) followed by a more rapid linear release between 3 and 5 h. Polyacrylamide gel electrophoresis revealed that the pattern of radioactive proteins present in the medium was different from and less complex than the tissue proteins. Substantial differences in protein patterns from different epididymal regions could be detected. The caput epididymidis was particularly active in secreting proteins characteristic of this region, whereas the corpus and cauda synthesized and secreted similar proteins. At least one of these proteins characteristic of the caput is stabilized by disulphide bonds. Short-term (9 day) castration resulted in reduced synthesis and secretion of several of these epididymal proteins. Testosterone administered after 9 days of castration reinitiated synthesis of some but not all of these epididymal proteins.
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PMID:Characterization and hormonal regulation of protein synthesis by the murine epididymis. 335 82

The concentrations of testosterone and its tissular metabolites were determined in testicular and epididymal tissue obtained from eleven male subjects (aged 65-85 years) after orchiectomy for prostatic cancer. The steroids were measured in different tissular compartments, i.e. testis, caput, corpus and cauda epididymis. The values (mean +/- SD; ng/g wet weight) were: Testosterone 724.0 +/- 286.0, 32.08 +/- 2.56, 41.45 +/- 1.77 and 32.24 +/- 2.14; 5 alpha-dihydrotestosterone 6.95 +/- 1.99, 9.76 +/- 2.33, 16.87 +/- 0.21 and 15.79 +/- 2.67; 5 alpha-androstane-3 alpha, 17 beta-diol 6.07 +/- 2.33, 2.17 +/- 0.24, 1.93 +/- 0.02 and 1.17 +/- 0.20; 5 alpha-androstane-3 beta, 17 beta-diol 56.66 +/- 20.97, 3.55 +/- 0.19, 2.21 +/- 0.27 and 3.34 +/- 0.32; estradiol-17 beta 5.36 +/- 3.0, 1.08 +/- 0.014, 1.44 +/- 0.038 and 1.47 +/- 0.03, respectively. Incubation of human testicular tissue with [3H]androst-5-ene-3 beta, 17 beta-diol or [3H]dihydrotestosterone showed that both androstane-diols were exclusively formed from dihydrotestosterone. Since high concentrations of 5 alpha-androstane-3 beta, 17 beta-diol are found in testicular tissue it is suggested that this steroid may be an index of seminiferous tubular function.
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PMID:Concentrations of unconjugated 5 alpha-androstane-3 alpha, 17 beta-diol and 5 alpha-androstane-3 beta, 17 beta-diol and their precursor in human testicular tissue. Comparison with testosterone, 5 alpha-dihydrotestosterone, estradiol-17 beta, and with steroid concentrations in human epididymis. 358 50

The concentrations of testosterone and dihydrotestosterone (DHT) were measured in the testis and in different segments of the epididymis and vas deferens of adult mice. There were marked regional variations in the concentrations of testosterone and DHT from the testis to the caudal part of the vas deferens. In the testis, testosterone was the predominant androgen (364 +/- 90 ng/g) while DHT was weakly represented (8 +/- 2 ng/g). Qualitative and quantitative changes occurred in epididymis: DHT was the main steroid in the caput (29.3 +/- 2.7 ng/g) and corpus (33.1 +/- 4.4 ng/g) while testosterone and DHT were in similar quantities in the cauda (18.6 +/- 2.6 and 19.0 +/- 2.7 ng/g, respectively). The proximal region of the vas deferens contained higher amounts (71.4 +/- 8.0 ng/g) of androgens (testosterone + DHT) than did the caput epididymidis (39.1 +/- 3.3 ng/g). Testosterone was the predominant androgen in each part of the vas deferens and its concentrations decreased from the proximal (64.5 +/- 7.5 ng/g) to the caudal (26.9 +/- 4.3 ng/g) region. Castration and section of the efferent ducts of the testis showed that the epididymis received testosterone essentially via the blood supply and that epididymal DHT was produced locally from circulating testosterone.
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PMID:Regional differences in the testosterone to dihydrotestosterone ratio in the epididymis and vas deferens of adult mice. 370 98

Radioimmunoassays were established for the measurement of total androgens and the specific measurement of testosterone and 5 alpha-dihydrotestosterone in peripheral plasma of the brush-tail possum. Androgen concentrations were measured in blood collected from indwelling jugular cannulae to determine whether the normal pattern of androgen secretion in this species was episodic and to attempt to relate total androgen and the pattern of testosterone secretion to the changes previously reported in prostatic, but not epididymal, weight in the breeding season. Blood was collected from restrained animals at varying time-intervals during daylight hours and darkness. Despite an apparent good adaptation to the sampling procedure there was generally a progressive decline in plasma androgen level during the collection period. This was true for animals bled during or out of the breeding season. There was no significant seasonal effect on the androgen concentration in the initial blood sample. When less restraint was used, two of three animals showed fluctuations in androgen levels over the 7-h sampling period. Testosterone levels in blood obtained by cardiac puncture were four- to nine-fold higher than those of 5 alpha-dihydrotestosterone but levels of these androgens in samples obtained during the breeding season were not significantly different from those obtained out of season. The results do not argue for a pulsatile release of testosterone in the possum but do demonstrate a marked capacity for changes in the peripheral androgen concentration. There was a poor correlation between testosterone and 5 alpha-dihydrotestostosterone levels and prostatic weight.
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PMID:Peripheral androgen levels in the male brush-tail possum (Trichosurus vulpecula). 398 24


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