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

The potential for the chemosterilant 1,2-dibromo-3-chloropropane (DBCP) to reduce male fertility by acting at a site in the genital tract beyond the testis was evaluated in male, Fischer 344 rats. A single sc treatment with 100 mg/kg DBCP reduced fertility in male rats 2 to 7 days postexposure without affecting mating frequency. Doses of 10, 20, or 40 mg/kg DBCP given sc once daily for 7 days caused a dose-dependent reduction in the metabolism of glucose to CO2 by epididymal sperm, as measured in vitro. Conversion of glucose to lactate was not reduced, indicating inhibition of energy metabolism at a step post-glycolysis. No clinical signs of toxicity were observed in these studies. Direct addition of DBCP to epididymal sperm being incubated in vitro also inhibited the metabolism of glucose to CO2. Inhibition was concentration related, and the minimal inhibitory concentration was 0.316 mM. These data indicate that DBCP may cause a nearly immediate infertility via a direct effect on post-testicular sperm. A possible mechanism of this infertility is inhibition by DBCP of glucose metabolism in the ejaculated sperm.
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PMID:1,2-dibromo-3-chloropropane (DBCP)-induced infertility in male rats mediated by a post-testicular effect. 663 94

Ethanol is generally regarded as a reproductive toxin. However, the mechanism(s) of ethanol-induced infertility remain poorly understood. As male fertility depends upon the ability of spermatozoa to fertilize ova, it was the purpose of the present study to examine the effects of chronic ethanol treatment on several parameters related to sperm fertility. Male C57Bl/6J mice of proven fertility were administered liquid diets as follows: 5% (v/v) ethanol for either 1) 5 weeks; 2) 10 weeks; 3) 20 weeks; or 4) 6% (v/v) ethanol for 5 weeks. After each treatment, epididymal spermatozoa were evaluated with respect to quantity, motility, morphology and the ability to fertilize. A biphasic effect on sperm content was noted: 5- and 10-week treatments with 5% ethanol increased content by 80 and 65%, respectively, whereas 20-week treatment with 5% ethanol and 5-week treatment with 6% ethanol decreased content by 52 and 71%, respectively. Although the proportion of motile spermatozoa was unaffected by ethanol, average forward progression velocity was reduced, the effect being dependent on ethanol dose and duration of exposure. Similarly, the frequency of abnormal spermatozoa was increased; 20-week treatment with 5% ethanol and 5-week treatment with 6% ethanol increased the frequency of sperm morphological anomalies by 50 and 40%, respectively. Fertility of spermatozoa was reduced as a function of ethanol dose and duration of exposure. The ability of sperm to fertilize mouse ova in vitro was reduced by 34% (P less than .02) and 62% (P less than .001) subsequent to 20-week treatment with 5% ethanol and 5-week treatment with 6% ethanol, respectively. An animal model has been developed which describes ethanol-induced male infertility. The degree of reproductive impairment varies with the amount of ethanol ingested, and the duration of ethanol exposure. The continuum of effects should make possible the evaluation of putative mechanisms of male sterility resulting from chronic ethanol consumption.
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PMID:Ethanol-induced male infertility: impairment of spermatozoa. 668 42

The intragastric administration of homologous strain epididymal sperm to adult virgin NZBW (Rt 1) female rats was shown to induce short-to long-term infertility. Infertility was associated with an early rise of genital secretory fluid IgA antisperm antibody preceding mating.
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PMID:Effect of ingested sperm on fecundity in the rat. 671 50

Recent technologic advances in the manufacture of suture materials, coupled with the employment of magnification during meticulous surgery, have made possible hitherto unobtainable successes with epididymovasostomy in the management of infertility due to congenital and inflammatory epididymal obstructions. Techniques of surgery and results in 115 cases of epididymovasostomy are discussed.
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PMID:Magnified surgery for epididymovasostomy. 671 67

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

Vasectomy is a rapid, inexpensive, 1-time method of birth control that has been chosen by 50 million men, 3/4 of whom live in the US, India, and South Korea. Although the operation has found little favor in Mediterranean countries, it is gaining interest in some countries of Latin America and the Middle East. Vasectomy can be performed on an ambulatory basis using local anesthesia and is associated with a very low rate of morbidity and almost no mortality. At present it is reversible in only about 25-35% of cases. A dialogue between the urologist and the patient is of the utmost importance to rule out any possible medical contraindication and to insure that the patient understands the permanence of the procedure and has chosen it voluntarily. The rate of complications of all types in different series varies from 1-122/1000 operations, with hematoma, infection, and epididymitis the most common. Spontaneous reanastomosis occurs in .1-.3% of cases. Some studies have minimized the probability of negative psychosocial consequences such as impotence or loss of libido resulting from the operation, stating that many couples have improved sexual relationships and that fewer than 1% of men express regret at not being able to father additional children, while other studies suggest more widespread reactions of insomnia, depression, hypochondriacal troubles, or sexual symptoms. Negative reactions occur most frequently in men who have not been adequately prepared psychologically for the procedure. Several prospective studies in men undergoing vasectomy have failed to demonstrate changes in testicular volume or in histologic status of the testicular parenchyma several years after operation, although changes at the epididymal level may occur. Although no absolute proof exists, it is likely that the presence of antisperm antibodies in the serum or seminal fluid after vasectomy plays a role in the persistent infertility of men undergoing sterilization reversal operations. The immunological effect of vasectomy on other organs and systems is a subject of controversy. The possible relationship between vasectomy and atherosclerotic disease also remains to be elucidated.
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PMID:[Vasectomy. Advantages, complications and consequences]. 685 68

Persistent infertility after vasectomy reversal by vasovasostomy may be due to irreversible changes in epididymal physiology, producing morphologic abnormalities of the sperm tail. Specimens from 29 men with persistent infertility following vasectomy reversal were analyzed and sperm motility and morphology were evaluated. the percentage of motile sperm was below normal in 23 specimens. Swimming speed evaluation on 20 specimens showed only 4 were below the normal range. In 19 of the 29 specimens, 10% or more of the sperm cells examined were characterized by a normal head and a coiled or shortened tail. Within this group, the percentage of sperm with tail abnormalities ranged from 2-64%, with a mean of 18.1%. The appearance of sperm tail abnormalities in conjunction with normal or high sperm concentrations suggests a disturbance of epididymal physiology. The epididymal environment is required for the final maturation of spermatazoa and the acquisition of normal motility and fertilizing ability. The study results suggest that these epididymal functions may be impaired in some men after vasectomy. A case report of a 32 year old man who had a vasectomy 7 years prior to referral to the evaluation group, and a successful vasovasostomy 2 years prior, revealed only 20% of the sperm evaluated in the initial specimen had the normal head and tail shape. His semen volume was 3.5 ml with a sperm concentration of 250 million/ml. 25% of the sperm were motile. Reexamination of the semen 8 times during the next year showed no significant changes. The cervical mucus penetration test showed no abnormalities of the sperm-cervical mucus interaction. When the motile sperm were spearated from the immotile cells and incubated with zona-free hamster eggs, all of the eggs were penetrated. Attempts were unsuccessful to isolate sufficient numbers of motile cells for artificial insemination, however, a normal pregnancy was conceived 1 year after the initial evaluation without additional therapy. One other man from the group also produced a pregnancy. It is suggested that the morphologic abnormalities may not confer sterility on the affected individual even when present in the majority of sperm cells, as indicated by the ability of sperm with normal tails to fuse with zona-free hamster eggs in vitro.
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PMID:Abnormalities of sperm morphology in cases of persistent infertility after vasectomy reversal. 709 58

The majority of spermatoceles originate in retention cysts of the vasa efferentia. Cystic embryonic remnants of the testis and epididymis are not so frequent. Only 10 of 20 patients undergoing surgical treatment of unilateral, singular spermatoceles preoperatively showed normozoospermia. Excision of the spermatocele in more than 50% of our patients caused permanent deterioration of their spermiogramm. The number of sperms was reduced to less than the half of the preoperative counts. Obstruction of the epididymal duct caused by postoperative cicatrices is thought to be the reason. In consequence of these results operative treatment of spermatoceles should be though over. Our series clearly shows that the dissection of a spermatocele by no means should be practiced by way of treating infertility.
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PMID:[Dissection of spermatoceles and fertility (author's transl)]. 719 Nov 62

Pressure-mediated effects of vasectomy on the epididymis and resolution of this effect via microsurgery of the epididymis are reported, and a technique of vasectomy modified to limit these pressure effects, making vasectomy more reversible, is suggested. Assuming mastery of microsurgical techniques for vas reanastomosis, the lack of which is one reason for low reversibility of vasectomy, other problems are still encountered that result in low sperm counts and demonstrable infertility. All vasectomies produce micromechanical, pressure-induced changes; 1000 vasovasectomies observed through the operating microscope always showed some degree of dilatation of the lumen of vas deferens and some congestion of the epididymis with dilatation of the epididymal tubule. Rather than augmenting infertility, the presence of a sperm granuloma seems to be a safety valve that decompresses the vas and prevents build-up of excessive pressure; this microscopic study discovered epididymal blowouts with extravasation of sperm from the epididymal tubule into the interstitium, causing secondary obstruction. Simple suture of the vas deferens is not sufficient for reanastomosis, but suturing of the inner lumen to the vas directly to the one cut epididymal tube leaking sperm must be performed. Open-ended vasectomy has a greater chance of reversibility as well as greater likelihood of spontaneous recanalization, a problem with solutions if research is started.
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PMID:Reversal of vasectomy and the treatment of male infertility. Role of microsurgery, vasoepididymostomy, and pressure-induced changes of vasectomy. 721 Mar 54

Bilateral insertion of silastic capsules releasing 38-44 micrograms norethisterone enanthate/24 h into the epididymal fat-pads was found to induce complete azoospermia leading to infertility in adult male rabbits 8 weeks after insertion of the progestin implants. The treatment did not exert any inhibitory effects on the libido and sexual behaviour of the animals as judged by objective parameters of mating. Further, the failure of the hormone-releasing implants was not found to exert any adverse effects on the embryos and pregnancy as indicated by the delivery of normal pups to females mated with implant-bearing males 3 weeks after the insertion of 'epididymal' implants.
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PMID:Long-term regulation of male fertility by norethisterone enanthate 'epididymal' implants: effect on libido and fertility of rabbits. 728 37


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