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PubMed1984

Biological determination of inhibin in rat ovarian-cell culture medium.

Rat ovarian-cell culture medium contains steroids and inhibin material that are able to influence basal and LHRH-stimulated secretion of FSH and LH from dispersed pituitary cells. Studies on procedures to remove steroids, such as ethyl acetate extraction and charcoal: dextran adsorption, showed that adsorption of the culture medium with 0.5 to 1.0% charcoal and 0.05 to 0.1% dextran, respectively, was the optimal method to eliminate most of the steroids in the medium without a detrimental effect on inhibin activity. The inclusion of serum or bovine albumin in the culture medium after the culture protected the inhibin from adsorption by the charcoal: dextran treatment. The inhibin present in the rat ovarian-cell culture medium treated with 1.0% charcoal: 0.1% dextran behaved like the inhibin reference standard (from rete testis fluid of the sheep: RTFS) in the basal secretion of FSH and the LHRH-stimulated secretion of FSH and LH in the in-vitro bioassay.

Adsorption↗
PubMed1990

Re-examination of the presence of alpha-lactalbumin in the epididymis of the rat.

Using an assay for alpha-lactalbumin in which galactosyltransferase activity was stabilized and a tissue phosphatase inhibitor was present, no evidence was found for alpha-lactalbumin-like activity in rat epididymal tissue, epididymal fluids or medium from cultured epididymal epithelial cells with either glucose or N-acetylglucosamine as acceptor. However, when assay conditions were suboptimal, apparent transfer of radioactivity to both acceptors could be demonstrated in the epididymis and other tissues. In these assays the amount of alpha-lactalbumin registered was linearly correlated to the extent of stimulation of alpha-lactalbumin added exogenously to tissue extracts as internal standards. When rete testis fluid from rats was used as source of galactosyltransferase under suboptimal conditions, no transfer to glucose was demonstrable in epididymal fluid and an apparent decreased transfer to N-acetylglucosamine could be explained by increases in (pyro)phosphatase activity. Putative alpha-lactalbumin activity in the epididymis may be an artefact of unoptimized assays.

Acetylglucosamine↗
PubMed2006

Successful transplantation of bovine testicular cells to heterologous recipients.

While heterologous germ cell transplantation was successful in pigs and goats, autologous transplantation alone has been reported to result in donor-derived spermatogenesis in cattle. The objective of this study was to investigate whether the transplantation of heterologous germ cells could result in colonization of recipient testes in cattle of different breeds. Testicular cells were isolated from 8 Bos taurus donor bull calves and then transferred into 15 Bos indicus-cross bull calves. All animals were prepubertal, donors were aged 5-7 months and recipients 5-11 months, and scrotal circumferences ranged from 15 to 22 cm. Single cell suspensions of donor testicular cells, prepared by enzymatic digestion, were labelled with fluorescent dyes PKH26 or CFDA-SE, before transfer into the rete testis of recipients under ultrasonographic guidance. To assess the longevity of colonization by donor cells, recipients were castrated 2-30 weeks after cell transfer. Donor cells were observed in 15/25 (60%) of the testes that received PKH26-labelled cells, whereas no CFDA-SE-positive cell was identified in any recipients. The maturity of the donors or recipients (measured by scrotal circumference) did not affect colonization potential. In freshly isolated tubules, clumps of PKH26-positive cells were observed, which indicated either cell division or extensive local colonization of specific areas of the tubules. In frozen sections, PKH26-positive cells were identified on the seminiferous tubule basement membrane, which indicated that these cells had successfully migrated from the tubule lumen and were likely to be spermatogonia. We conclude that PKH26 was more suitable for labelling donor testis cells and donor cells can be identified up to 6 months following transfer. These results indicate that allogeneic transplantation of testicular cells can occur between Bos taurus and Bos indicus cattle. Further studies will investigate functionality of transferred testicular cells.

Animals↗
PubMed1986

Sexual dimorphism in immunoneutralization of bioactivity of rat and ovine inhibin.

Inhibin was partially purified from bovine follicular fluid using chromatography on immobilized Procion Red 3B and anion-exchange chromatography. Ovariectomized Texel ewes were immunized against the inhibin-containing fraction from the Procion Red 3B column and the immune response was subsequently boosted with similar fractions or with the preparation obtained from the anion-exchange column. The potencies of the resulting antisera were evaluated in an in-vitro bioassay system for estimating inhibin activity, using dispersed rat pituitary cells. The antisera were found to inhibit the bioactivity of inhibin preparations from ovarian follicular fluid of bovine, porcine, ovine or human origin, as well as inhibin activity in ovine testicular lymph and rete testis fluid, in culture media from rat granulosa and rat Sertoli cells and in homogenates of rat ovaries and testes. These results indicate that the inhibin molecules from several species contain a common bioactive moiety. The results also showed that the antiserum was more effective in neutralizing inhibin activity from ovarian than from testicular sources in both sheep and rat, indicating a sex-related difference in the inhibin molecules within a species.

Animals↗
PubMed1990

The role of angiotensin-converting enzyme in the rat epididymis.

In order to investigate the role of renin angiotensin in the epididymis, angiotensin-converting enzyme (ACE) activity and angiotensin I (AI) and angiotensin II (AII) concentrations were measured in the male reproductive tract and blood serum of the rat. High ACE activity was detected in the rat epididymis, with a major part of the activity being associated with epididymal spermatozoa. When spermatozoa were prevented from entering the epididymis by efferent duct ligation, the ACE activity in the epididymis was greatly reduced. The epithelial cells lining the epididymal duct were also shown to possess ACE activity which was dependent upon circulating androgens. Treatment of male rats with captopril at a single oral dose (20 mg/kg) significantly inhibited the ACE activity in the blood serum but had no effect on the activity of the epididymal fluid. The intraluminal ACE was protected from the circulating captopril by the blood-epididymis barrier. Long-term treatment with captopril (20 mg/kg per day, 8 weeks), however, caused an increase in blood serum ACE activity but was without effect on intraluminal ACE. The fertility and fecundity of male rats after treatment were apparently normal. The concentrations of AI and AII were high in the epididymal plasma and epididymal cell when compared with the respective concentrations in blood serum. The intraluminal AII concentration found (13 nmol/l) was close to the threshold concentrations that stimulate anion (and fluid) secretion in cultured epididymal epithelium in vitro. The high intraluminal AII concentration could not have been derived from the testicular fluid or spermatozoa since the rete testis fluid and sperm contained little AII.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin I↗
PubMed1991

Pituitary and testicular responses of beef bulls to active immunization against inhibin alpha.

Prepubertal crossbred beef bulls served as controls or were actively immunized against the N-terminal, 30-amino acid synthetic fragment of porcine inhibin alpha, pI alpha (1-30). Antibody titers were detected in sera (greater than 40% B/BO in sera diluted 1,000-fold) but not in rete testis fluid of 390-d-old bulls. Serum FSH and inhibin remained static during a 5-h intensive bleed; inhibin was not acutely affected by a 15-fold LH rise and a threefold FSH rise induced by exogenous GnRH. Serum FSH, but not LH or testosterone, was consistently elevated (P less than .05) in immunized bulls compared with control bulls. Neither pituitary weight, pituitary gonadotropin content nor pituitary FSH/LH ratios were affected (P greater than .10) by pI alpha(1-30) active immunization. Testicular sperm density was greater (60 x 10(6) vs 45 x 10(6) sperm/g testis; P less than .10) in immunized bulls, but testes weight, epididymides weight and total daily sperm production remained unchanged. These results suggest that inhibin is important for regulation of FSH secretion and testicular function. Immunization with suitable inhibin vaccines may improve bull fertility.

Animals↗
PubMed1981

Concentrations of sperm, protein and a sperm membrane glycoprotein within boar epididymal luminal fluids.

Boar rete testis fluid and luminal contents from nine epididymal segments were collected for analysis. From proximal to distal, segments were designated A, B, C (caput), Da, Db, Ea (corpus) and Eb, Fa, Fb (cauda). Concentrations of sperm, protein and soluble sperm membrane glycoprotein S2P3 were lowest in the caput epididymidis (region A) and highest in the proximal corpus epididymidis (region Da). At region Da, approximately 94% of the fluid that had entered the epididymis had been reabsorbed. More total protein was found in the luminal fluid of region Da than could be accounted for on the basis of concentration via fluid removal. The proximal cauda epididymidis was the major luminal protein-removing region. However, large amounts of glycoprotein S2P3 were removed from the luminal fluids during passage through the caput epididymidis, and smaller amounts were removed during passage through the cauda epididymidis.

Animals↗
PubMed1981

Contractility of seminiferous tubules as related to sperm transport in the male.

The mammalian testes have several mechanisms to propel the nonmotile spermatozoa in the seminiferous tubules through the rete testis into the epididymis. These include (a) contractions of the testicular capsule and the seminiferous tubules and (b) fluid flow through the excurrent ducts resulting from active transport of fluids and electrolyte into the seminiferous tubules from the extracellular space. The efflux of fluids and sperm from the testis appears to closely parallel spermiation. An increased output of fluid may result from prostaglandins (PGF2 alpha) and possibly oxytocin (not all species respond to oxytocin) as a result of capsular contractions compressing and expelling the fluid from the tubules. Seminiferous tubular contractions do not result from nervous stimulation but are linked to PGs and cyclic nucleotide generation. They are regulated to some extent by androgens and the lesser response of the tubules to 5 alpha-dihydrotestosterone compared to testosterone can be explained by their interaction with androgen binding protein and their action on phospholipase A2 activity for PG synthesis.

Androgen-Binding Protein↗
PubMed1986

Pregnancy-associated plasma protein-A concentrations in men with testicular and prostatic tumors.

Pregnancy-associated plasma protein-A (PAPP-A) is a macromolecular glycoprotein produced during pregnancy by the trophoblast and the decidua. It is not specific to pregnancy, since immunoreactive PAPP-A is in the circulation of normal women and men and in seminal fluid. Immunohistochemically, PAPP-A is localized in some Leydig cells, in the epididymis, in the rete testis, and in seminal vesicles. This study was conducted to learn whether circulating levels of PAPP-A can be used as a marker for the monitoring of human testicular cancer. PAPP-A was increased only in certain nonseminomatous germ cell tumor [malignant teratoma undifferentiated (MTU) + seminoma, malignant teratoma intermediate (MTI)], but the overlap with the normal values was too big for PAPP-A to have any clinical significance. After orchidectomy or prostatectomy, PAPP-A decreased but the levels were were similar to those of normal men. In men, PAPP-A can be produced by certain nonseminomatous germ cell tumors, but its origin in disease-free males is probably not the testis or the prostate.

Adenoma↗
PubMedDate not supplied

Pathology of osseous and genitourinary lesions of Proteus syndrome.

A male patient followed from the age of 3 to 25 years was eventually diagnosed as having Proteus syndrome. He was born with linear epidermal nevi of the neck and forearm and presented with macrodactyly of the right hand and progressive hemihypertrophy of the right lower limb recurring after multiple reduction operations. The bone ends showed disorderly overgrowth of hyaline and fibrocartilage mixed with collagen and bone, and early differential diagnoses included Ollier's disease. The child also had vertebral anomalies, scoliosis, a bony protrusion of the cranial vertex, and strabismus. In the second decade he developed gyriform swelling of the soles, retinopathy, bilateral papillary cysts of the epididymis, and a giant cyst of the left kidney with complex glandular foci. At 22 years a 3-cm meningioma containing adipose tissue was resected, and at 24 years a 3-cm cellular nodule of the rete testis with hyperchromatic foci, probably an adenoma, was removed. The features of Proteus syndrome were those of hyperplasia and neoplasia of mostly mesodermal tissues. Unlike other reported cases, overgrowth of a finger recurred at 25 years.

Adult↗
PubMed1991

Effects of scrotal insulation on viability characteristics of cryopreserved bovine semen.

The effect of a 48-h scrotal insulation on spermatozoal viability (motility and acrosomal integrity), before and after semen cryopreservation, was studied in six young Holstein bulls whose semen was collected twice in succession at 3-d intervals. Motility and acrosomal integrity were measured before and after incubation of semen at 37 degrees C for 3 h. For assessment of results, collection days were grouped: period 1 (control) = d -6, -3, and 0, where d 0 = initiation of scrotal insulation after semen collection; period 2 = d 3, 6, and 9 (sperm presumed in the epididymis or rete testis during scrotal insulation); period 3 = d 12, 15, ... 39 (sperm presumed in spermatogenesis during scrotal insulation). Semen was cryopreserved each collection day until morphologically abnormal cells exceeded 50% of the ejaculate (d 12 to 21). Semen viability before and after freezing was lower in period 3 than in period 1 (P less than .05). These differences coincided with the appearance in period 3 of abnormal sperm morphology and depressed undiluted semen motility, which began on d 12 (P less than .01). Semen collected during period 2 that was extended but unfrozen did not differ from that collected during period 1 in morphology or viability. However, for frozen semen, period 2 was significantly poorer than period 1 for both viability measurements, but only after incubation for 3 h at 37 degrees C postthaw (P less than .05). We conclude that epididymal sperm are adversely affected by elevated testicular temperatures, as noted by their decreased ability to maintain motility and acrosomal integrity following cryopreservation.

Acrosome↗
PubMed1976

[Chronology of development of the genital tract of the calf fetus].

The chronology and the modalities of the differentiation of the genital apparatus were studied in 187 calf fetuses whose insemination age was exactly known (between 32 and 110 days). Male. In the male, the first seminiferous cords form around days 41-42, the interstitial cells appear 2 or 3 days later. From days 60-70 on, the rete testis is made of tubules with an open lumen, which connect the seminiferous cords. The masculinisation of the external genitalia begins as early as day 47 by a rapid increase of the anogenital distance: on day 60, the penis opens under the umbilicus and the scrotum is well differentiated. The regression of the Müllerian ducts starts at the level of their anterior (tubal) part on day 50, when their diameter decreases. From day 58 on, the oviducts become discontinuous and they are almost completely absent by day 63; the uterine horns and the vagina have dissappeared by day 80. The masculinization of the internal genitalia occurs during two phases: 1) between days 56 and 58: the early buds of the seminal vesicles and of the prostate appear, as well as the first differences at the level of the urogenital connections and of the Cowper's glands; a supra-urethral diverticulum develops at the level of the posterior prostatic urethral flexure; the non sexual urethra remains short. 2) After day 70 take place: the differentiation of the epididymides the branching of the seminal vesicles and the stabilization of the Wolffian ducts (after a transitory diminution of their diameter between days 60 and 80). Female. In the female, sexual organogenesis proceeds later than in males. The Müllerian ducts (which show a transitory reduction of their diameter at their tubal level between days 50 and 60) develop steadily after day 60 at the level of their uterine horns and of the vagina; simultaneously the non sexual urethra lengthens rapidly. A suburethral diverticulum, which is absent in the male, develops at the level of the urogenital connections, between days 60-70. The regression of the Wolffian ducts takes place after day 70 when the mesonephros disappear; they first become discontinuous in their median part (at the uterine level) between days 77-80, but important remains of these ducts still persist on day 110, in the posterior part of the vagina. The first primordial ovarian follicles form only after day 100 approximately.

Animals↗
PubMedDate not supplied

Reproductive tract secretions and bull spermatozoa contain different clusterin isoforms that cluster cells and inhibit complement-induced cytolysis.

Clusterin from bull rete testis fluid (RTF), cauda epididymal fluid (CEF), and octyl-beta-D-glucopyranoside extract of cauda epididymal sperm (CES) was identified and characterized using monoclonal and polyclonal antibodies (Abs) developed against ram clusterin and a beta-subunit-specific oligopeptide of porcine clusterin. One-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis and western blotting showed that bovine RTF clusterin had dimeric and monomeric molecular weights (M(r)s) of approximately 94 kDa and of 42 and 43 kDa, respectively. Clusterin in CEF and CES had similar dimeric M(r)s (74 kDa). Reduced CEF clusterin appeared as three monomers (M(r)=40, 39, and 38 kDa), whereas reduced CES clusterin appeared only at M(r)40 kDa. Enzymatic deglycosylation resulted in similar M(r)s of clusterin from RTF, CEF, and CES. The M(r) of RTF clusterin decreased from 94 kDa to 51 kDa, indicating a carbohydrate content of 45%. After deglycosylation, the M(r) of the CEF clusterin decreased from 74 kDa to two distinct bands at 51 and 50 kDa (with carbohydrate contents of 31 and 32%, respectively), suggesting that two isoforms of the heterodimeric protein are present because of the two isoforms of the alpha-subunit. Under nonreduced conditions, a beta-subunit-specific Ab reacted with M(r) of 36-38 kDa, indicating the existence of free clusterin beta-subunits in CES. RTF, CEF, and CES extracts all caused mouse fibroblastic L-cell aggregation. CEF cell aggregation was inhibited by Hyb-17 Ab but not by other Abs. Both RTF and CEF caused a dose-dependent inhibition of complement-induced cytolysis, although RTF clusterin was more potent than CEF clusterin. We conclude that several isoforms of clusterin occur in the bull reproductive tract and that the variation in carbohydrate content among these isoforms may affect the biological or functional activity of the protein.

Animals↗
PubMed1999

[Benign testicular tumors in children. Value of simple tumorectomy].

From 1984 to 1999, the authors observed 18 intratesticular tumours, 13 of which corresponded to benign lesions. The objective of this study is to define preoperative and intraoperative criteria of benign lesions in order to allow conservative management (simple excision or enucleation) and to analyse the results of this treatment. The 13 boys of this series were between the ages of 5 months and 14 years (mean: 7.1 years). The lesion presented as scrotal swelling in 12 cases and gynaecomastia in 1 case. Tumour markers (alphafoetoprotein, beta HCG) were at the limit of normal for age. Ultrasonography was performed in every case. In each case, treatment consisted of primary exposure of the pediclc with clamping then exteriorization and macroscopic examination of the lesion. Frozen section examination was performed in 11 cases. Treatment consisted of 9 enucleations and 4 orchidectomies. The final histology concluded on epidermoid cyst or simplified teratoma with exclusively ectodermal development in 4 cases, multi-differentiated teratoma in 2 cases, sex cord tumour in 2 cases, simple cyst in 2 cases, rete testis dysplasia in 1 case, cavernous haemangioma in 1 case, and vestigial cyst in 1 case. There was no discordance between the final histological examination and the frozen section examination. The mean follow-up is 4.4 years. No secondary atrophy and no local or distant recurrence was observed in the 9 cases of enucleation. In conclusion, testicular tumours are often benign in children. Selection based on a body of clinical, laboratory, radiological and frozen section histological evidence should allow carcinologically safe conservative surgery with an aesthetic, psychological and functional benefit for the child.

Adolescent↗
PubMedDate not supplied

Posttesticular antifertility action of triptolide in the male rat: evidence for severe impairment of cauda epididymal sperm ultrastructure.

A variety of active diterpene epoxides, including the triptolide (isolated from Tripterygium wilfordii) have been reported to cause infertility in male rats. Previously, we showed that oral administration of triptolide at a dosage of 100 microg/kg per body weight for 70 days completely inhibited fertility in male rats, with little or no demonstrable detrimental effect on spermatogenesis and Leydig cell function as determined by testicular light microscopic appearance and serum and intratesticular testosterone levels. Despite the apparent absence of effects on the testes, cauda epididymal sperm were abnormal, with complete cessation of sperm motility and some reduction in sperm numbers. This study was undertaken to provide additional insight into the subcellular sites and possible mechanisms of action of this compound using ultrastructural analysis of the testes and epididymidis. The most striking effect of triptolide treatment was observed in sperm in the epididymis. In rats rendered infertile with 100 microg/kg per body weight of triptolide daily for 70 days, virtually all cauda epididymal sperm exhibited complete absence of plasma membrane over the entire middle and principal piece, premature decondensation of the nuclei, and disorganization of the mitochondrial sheath with many vacuolated mitochondria. No ultrastructural differences in the epididymal epithelium were observed between control and triptolide-treated rats. The testes appeared to be mildly affected after triptolide treatment but exhibited only subtle ultrastructural defects in the germ cells. The findings of severe impairment of cauda epididymal sperm ultrastructure, along with minimal discernible abnormalities in the fine structural cytology of the testes, further suggest that the site of action of this compound is posttesticular and may be confined to the cauda epididymal sperm. However, we cannot rule out an effect of triptolide that occurs during germ cell maturation but is delayed in its manifestation or triggered at the rete testis and epididymal level.

Animals↗
PubMed2000

The paratesticular region: histoanatomic and general considerations.

The paratesticular region includes the testicular collecting system, the testicular tunics, and spermatic cord. For the purpose of discussion in this issue, the rete testis is also considered part of the paratestis, although it is principally intratesticular in location. The embryologic origins of the paratesticular components and their detailed anatomic and histologic features are presented to provide a background to better understand the pathologic processes affecting the paratestis. A wide variety of cysts, hyperplasias, neoplasms, and tumor-like conditions may affect the paratesticular region, at times resulting in challenging problems in differential diagnosis. An approach to the paratesticular causes of an intrascrotal mass lesion is presented.

Embryonic and Fetal Development↗
PubMed2001

Intratesticular transplantation of testicular cells from leukemic rats causes transmission of leukemia.

A rat T-cell leukemia model was used to study the safety of germ cell transplantation as a mean of preventing infertility in males undergoing gonadotoxic cancer treatment. Donor germ cells were harvested from the testes of terminally ill leukemic rats and were either used directly or cryopreserved and thawed before transplantation by rete testis microinjection. All rats transplanted with testicular cells from leukemic donors developed signs of terminal rat T-cell leukemia, whereas control animals remained healthy. Cryopreservation of the donor germ cells caused a 3- to 6-day delay in the terminal phase of leukemia. When a known number of leukemic cells were mixed with germ cells and microinjected into the testis, the rate of appearance of terminal leukemia was directly related to the number of transferred leukemic lymphoblasts. As few as 20 leukemic cells were able to cause a cancer relapse resulting in terminal leukemia 21 days after transplantation in three of five transplanted animals. Our results demonstrate that germ cell transplantation with the presently used techniques is not safe enough for clinical use. Improved methods for purging testicular specimens of cancer cells or totally new approaches with transient xenogenetic host models to detect contamination of malignant cells must be developed before this technique can be offered to patients without fear of disease relapse.

Animals↗
PubMedDate not supplied

Localization of clusterin on freeze-preserved bull spermatozoa before and after glass wool-sephadex filtration.

Clusterin is a major protein in bull reproductive tract secretions and sperm membrane extract. A polyclonal antibody was produced against clusterin from bull cauda epididymal fluid (CEF) and used for the localization of the protein on bull spermatozoa. Immunoblotting of unreduced bovine samples showed that the anticlusterin antibody reacted with a protein of approximately 94- to 100-kd in rete testis fluid (RTF), a approximately 57- to 76-kd protein in CEF, and with a approximately 57- to 60-kd protein from cauda epididymal sperm membrane extract. The antibody also reacted with stallion RTF and both ram CEF and RTF at relative molecular weights (Mr) that were consistent with the anticipated size of clusterin in these species. Less intense immunostaining was observed for a protein of about 2 times the predicted size of clusterin in unreduced ovine RTF, suggesting the presence of multimers of clusterin in ovine RTF. Also, a dimeric clusterin-sized protein was detected in reduced bovine CEF, suggesting the presence of unprocessed clusterin in bovine CEF. By immunofluorescence, clusterin was detected on only a small fraction of bull spermatozoa, which were morphologically abnormal. Neither permeabilization nor the method of dilution affected the reactivity of the antibody with spermatozoa (P > .05). Average clusterin-positive spermatozoa (CPS) in unpermeabilized, permeabilized, abruptly diluted, and gradually diluted semen were 10.1%, 11.3%, 15.0%, and 14.4%, respectively. CPS were eliminated from semen after filtration through glass wool-Sephadex (GWS) columns. Average CPS in unfiltered and filtered semen were 14.3% and 1.1%, respectively. We conclude that sperm clusterin in bull semen is associated with morphologically abnormal spermatozoa and that clusterin is implicated in the process of abnormal spermatozoa trapping in GWS columns. We suggest that the fraction of CPS in bull semen is a potential marker for poor semen quality.

Animals↗