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PubMed2003

Estrogen in the adult male reproductive tract: a review.

Testosterone and estrogen are no longer considered male only and female only hormones. Both hormones are important in both sexes. It was known as early as the 1930's that developmental exposure to a high dose of estrogen causes malformation of the male reproductive tract, but the early formative years of reproductive biology as a discipline did not recognize the importance of estrogen in regulating the normal function of the adult male reproductive tract. In the adult testis, estrogen is synthesized by Leydig cells and the germ cells, producing a relatively high concentration in rete testis fluid. Estrogen receptors are present in the testis, efferent ductules and epididymis of most species. However, estrogen receptor-alpha is reported absent in the testis of a few species, including man. Estrogen receptors are abundant in the efferent ductule epithelium, where their primary function is to regulate the expression of proteins involved in fluid reabsorption. Disruption of the alpha-receptor, either in the knockout (alphaERKO) or by treatment with a pure antiestrogen, results in dilution of cauda epididymal sperm, disruption of sperm morphology, inhibition of sodium transport and subsequent water reabsorption, increased secretion of Cl-, and eventual decreased fertility. In addition to this primary regulation of luminal fluid and ion transport, estrogen is also responsible for maintaining a differentiated epithelial morphology. Thus, we conclude that estrogen or its alpha-receptor is an absolute necessity for fertility in the male.

Animals↗
PubMed2004

Immunohistochemical examination of mucinous cystadenoma of the testis.

A case of mucinous cystadenoma of the testis in a 55-year-old man is reported. The tumor was confined to the testis and was clearly separated from the epididymis. There was no connection between the tumor cyst and the rete testis. The lumen of the cyst was lined with a single-layer of columnar cells interspersed with goblet cells. There was neither stromal invasion nor metastasis to other organs and there were no ovarian or germ cell neoplastic elements in the tumor. Immunohistochemical analysis revealed that MUC2, MUC5AC, carcinoembryonic antigen, CA19-9, CK7 and CK20 proteins were expressed on the tumor epithelial cells, whereas expression of MUC6, alpha-fetoprotein, CA125, human chorionic gonadotrophin, estrogen receptor, progesterone receptor, calretinin, chromogranin A, p53, cyclin D1 and bcl-2 proteins was absent. Ki-67 protein was weakly and sparsely expressed in the nuclei of epithelial cells. The mucinous cystadenoma in the present case, which was devoid of a connection to testicular appendices and had the immunohistochemical characteristics of gastrointestinal mucosa, might have originated from one-sided differentiation of teratoma cells.

Biomarkers, Tumor↗
PubMed1999

Expression of the RNA component of human telomerase in adult testicular germ cell neoplasia.

BACKGROUND: During human development, telomerase is repressed in most somatic cells, whereas it is maintained in male germline cells. Reactivation of telomerase has been associated with somatic cancers. To the authors' knowledge, the role of telomerase in germ cell derived malignancies has not previously been evaluated. METHODS: A radioactive in situ hybridization method was used to study the expression of the RNA component of human telomerase (hTR) in 22 cases of adult testicular germ cell neoplasia encompassing all major histomorphologic types. For precise cell identification, hTR in situ hybridization was combined with immunohistochemistry in select cases. RESULTS: Testicular germ cell tumors showed differential expression of hTR. The highest level of expression was seen in embryonal carcinoma. Seminoma and unclassified intratubular germ cell neoplasia exhibited moderate levels of expression. Yolk sac tumor was characterized by a range of expression, which mirrored its morphologic variation. Immature teratoma recapitulated the down-regulation of telomerase manifested during human embryogenesis. Mature teratoma represented the adult pattern of somatic repression. Notably, choriocarcinoma showed modest expression. The expression of spermatocytic seminoma was intermediate between that of classic seminoma and embryonal carcinoma. No difference in expression was evident between matching intratubular and invasive components. In nonneoplastic testis, hTR expression was down-regulated during spermatogenesis and was absent in spermatozoa. Expression was negligible in rete testis and interstitial Leydig cells, and low in epididymis. Unexpectedly, Sertoli cells, which are testicular accessory somatic cells, displayed the most intense expression observed in this study. CONCLUSIONS: In testicular germ cell tumors of young adults (and during spermatogenesis), hTR expression is down-regulated with differentiation, irrespective of the aggressiveness of the tumors. Spermatocytic seminoma, regarded as a low grade malignancy, shows moderately intense expression.

Adult↗
PubMedDate not supplied

Immunocytochemical localization of the Yf subunit of glutathione S-transferase P shows regional variation in the staining of epithelial cells of the testis, efferent ducts, and epididymis of the male rat.

Glutathione S-transferases (GSTs) are a family of isozymes that catalyze the conjugation of glutathione (GSH), a tripeptide found in all mammalian cells; this function plays a protective role, as the addition of GSH to an electrophile generally forms a less toxic product. The pi class of GSTs contains homodimers of the Yf subunit, also known as Yp or rat subunit 7; this subunit is found in high concentrations in the testis and epididymis. The objective of the present study was to localize immunocytochemically the Yf subunit in the testis and in the various regions of the epididymis using light, electron, and confocal microscopy. In the testis, immunoperoxidase staining was localized exclusively to Sertoli and Leydig cells. The low cuboidal epithelial cells of the rete testis and the sparse ciliated cells of the ductuli efferents were also immunoreactive. A distinct pattern of immunostaining for the Yf subunit was observed in the different regions of the epididymis. The proximal area of the initial segment showed intense reactivity localized to epithelial basal cells. Basal cells in the middle area of the initial segment were also reactive, as were a second unidentified population of cells located in the apical region of the epithelium. The epithelium, including both principal and basal cells, in the distal initial segment, intermediate zone, and proximal caput epididymidis showed a weak, moderate, or strong degree of reactivity, respectively. In the distal caput epididymidis, however, principal cells showed a checkerboard-like pattern of immunoreactivity, with some cells being intensely stained or faintly stained, whereas others were unreactive. Strikingly, in the corpus and proximal cauda epididymidis, intense immunostaining was localized exclusively over the epithelial basal cells. As viewed in the light and confocal microscope, the intensely stained basal cells showed extensive processes that covered most of the base of the epididymal tubule. Upon quantitation of the immunogold labeling density (the number of gold particles/microns2) in principal and basal cells of the different regions of the epididymis, we observed a sharp decline in immunogold labeling of principal cells coupled with a dramatic increase in labeling of basal cells as we progressed along the tissue, particularly in the transition from the caput to the corpus epididymidis. This study constitutes the first demonstration of a protein that is selectively expressed in epithelial basal cells of the corpus and proximal cauda epididymidis.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1999

Differential localization of inhibin subunit proteins in the ovine testis during fetal gonadal development.

Inhibins and activins are dimeric proteins that are involved in cell proliferation, apoptosis, and differentiation in a number of systems and have previously been detected in fetal testes of many species. This study used immunohistochemistry to examine the localization of inhibin alpha-, betaA-, and betaB- subunits during ovine testicular development from days 40-135 of gestation. Localization of inhibin betaA- and betaB-subunit messenger RNAs was confirmed by in situ hybridization. The results showed that there was differential localization of inhibin alpha-, betaA-, and betaB-subunits to specific cells in the ovine fetal testis from 40 days of gestation. All three inhibin subunits were present in Sertoli cells throughout gestation, whereas the rete epithelium and gonocytes did not express inhibin alpha-subunit. These data suggest that the fetal Sertoli cells have the capacity to produce all forms of inhibins and activins, i.e. inhibin A and B, and activins A, AB, and B, whereas the rete testis epithelial cells can only synthesize activin A. In the interstitium, the fetal Leydig cells expressed all three inhibin subunits, but this was restricted to the period between 40 and 90 days of gestation. Thereafter, inhibin alpha-subunit immunoreactivity was not observed in fetal Leydig cells, which suggests that only activin ligands are produced by Leydig cells during late gestation. Collectively, the data demonstrate that fetal ovine testes have the potential to produce the full repertoire of inhibins and activins from very early in testicular differentiation. The distinct and restricted localization of the various subunits to specific cells suggests that specific dimeric proteins have particular roles in the development and function of the fetal testis.

Animals↗
PubMed2000

Cystic testicular lesions in the pediatric population.

PURPOSE: We present the etiology, histological evaluation and management of all cystic lesions of the pediatric testis. MATERIALS AND METHODS: Illustrative cases from our experience are reported with a literature review of all possible diagnoses. RESULTS: Included in the differential diagnosis of cystic testis lesions in children are epidermoid cyst, dermoid cyst, prepubertal teratoma, juvenile granulosa cell tumor, cystic dysplasia of the rete testis, testicular cystic lymphangioma, simple cyst and cystic degeneration after torsion. Testis sparing surgery is feasible in many circumstances. CONCLUSIONS: Cystic lesions of the pediatric testis are rare but represent an interesting group of diagnoses. Patient age at presentation, examination features, tumor markers and sonographic appearance may assist in making a presumptive and occasionally definitive diagnosis preoperatively. Based on the likely diagnosis enucleation or partial orchiectomy may be considered when performed with frozen section histological assessment. A thorough understanding of potentially cystic testis lesions in children leads to the best management choices and often to preservation of a substantial portion of the affected testis.

Cysts↗
PubMed2005

Postnatal developmental changes in immunohistochemical localization of alpha-smooth muscle actin (SMA) and vimentin in bovine testes.

The present study demonstrates the postnatal developmental changes in immunohistochemical localization of alpha-smooth muscle actin (SMA) and vimentin in the bovine testis. In the peritubular myoid cells of seminiferous tubules and the sub-epithelial and stromal cells of straight tubules and the rete testis, alpha-SMA starts appearing at around 4 months of age. Peritubular alpha-SMA attains the continuous mature pattern at around 5 months of age whereas sub-epithelial and stromal alpha-SMA increases with advancing age. Vimentin is localized in the perinuclear zone of Sertoli cells, peritubular and vascular wall cells, a few interstitial cells, and in the basal part of the epithelia of straight and rete tubules. Developmental changes are only evident in the Sertoli cell vimentin, which is basal and weak at birth and increases moderately until 4 months of age. From around 5 to 8 months of age when the Sertoli cells are under morphological transformation, vimentin intensity is considerably increased and the characteristic vimentin extensions connect the Sertoli nuclei to the basal membrane. These extensions get shorter at around 9 month of age as the Sertoli nuclei are positioned basally. The mature Sertoli cell perinuclear vimentin is strong and stable without infranuclear extension. In conclusion, the age of appearance of alpha-SMA coincides with the onset of postnatal division of spermatogonia, and vimentin may play a key role in stabilizing Sertoli cell nuclei during their transformation in bovine.

Actins↗
PubMed2003

Germ cell transplantation in goats.

Transplantation of spermatogonial stem cells provides a unique approach for the study of spermatogenesis and manipulation of the male germ line. This technique may also offer an alternative to the currently inefficient methods of producing transgenic domestic animals. We have recently established the technique of spermatogonial transplantation, originally developed in laboratory rodents, in pigs, and this study was aimed to extend the technique to the goat. Isolated donor testis cells were infused into the seminiferous tubules of anesthetized recipient goats through an ultrasonographically-guided catheter inserted into the rete testis. Donor cells were obtained by enzymatic digestion of freshly collected testes from immature goats (either from the recipients' contralateral testis or from unrelated donors). Prior to transplantation, testis cells were labeled with a fluorescent marker to allow identification after transplantation. Recipient testes were examined for the presence and localization of labeled donor cells at 3-week intervals up to 12 weeks after transplantation. Labeled donor cells were found in the seminiferous tubules of all testes, comprising 10-35% of the examined tubules. Histological examination of the recipient testes did not reveal evident tissue damage, except for limited fibrotic changes at the site of needle insertion. Likewise there were no detectable local or systemic signs of immunologic reactions to the transplantations. These results indicate that germ cell transplantation is technically feasible in immature male goats and that donor-derived cells are retained in the recipient testis for at least three months and through puberty. This study represents the first report of germ cell transplantation in goats.

Animals↗
PubMed1989

Carcinoma in situ of the testis in infertile men. A histological, immunocytochemical, and cytophotometric study of DNA content.

Of 723 infertile men (128 with a history of cryptorchidism) whose testes were biopsied at the outer lateral face of the testis, five presented carcinoma in situ (CIS) in one testis. These testes were removed, serially sectioned, and examined by light microscopy. In order to evaluate whether only one or two biopsies are sufficient to diagnose CIS, before sectioning the testes four biopsies were taken at the anterior face, posterior face, superior pole, and inferior pole of the testis, respectively. Two of the five men had undergone orchiopexy in infancy and the testis contained tubules with Sertoli cells and isolated spermatogonia. CIS was also present in some tubules that were principally located near the rete testis. Of the four simulated biopsies, only that performed at the posterior face of the testis revealed CIS. The other three infertile men showed tubules with complete, although reduced, spermatogenesis, and tubules lined by Sertoli cells only. CIS was found in both types of tubules. These tubules with CIS formed lobules that extended throughout the testicular parenchyma. Most simulated biopsies performed in these three testes showed CIS. The average nuclear DNA content of CIS cells was about 4c in all testes. This content was similar both in tubules with complete spermatogenesis and in tubules with Sertoli cells only.

Adult↗
PubMed1985

The mammalian rete ovarii: a literature review.

The rete ovarii is the homologue of the rete testis. It develops from cells of mesonephric origin which immigrate into the developing gonad of the embryo. The mature form of the rete ovarii is generally found to be groups of anastomosing tubules lined by cuboidal or columnar epithelium. These tubules are usually located in the hilus of the ovary, but may extend through the medulla or be isolated in the mesovarium adjacent to the hilus. The rete is often continuous with the transverse ductules through which it contacts the longitudinal duct of the epoophoron. The rete ovarii is important in the control of meiosis in the maturing ovary. Cells of the rete ovarii differentiate to form granulosa cells as well. The rete is also credited with secretory capability, a hypothesis supported by the observation of secretory material in the lumina of the rete tubules in several species. Cysts have been observed in the rete ovarii of several species. The rete ovarii of the adult does not appear to be a functionless vestige as has been previously reported.

Aging↗
PubMed1996

The penetration of chromium-EDTA from blood plasma into various compartments of rat testes as an indicator of function of the blood-testis barrier after exposure of the testes to heat.

The concentration of chromium51-EDTA in blood plasma after an intravenous infusion was found to be about 40 times that present in rete testis fluid and 20 times that in the additional seminiferous tubular fluid resulting from ligation of the efferent ducts. These values indicate the effectiveness of the blood-testis barrier to small water-soluble molecules, like Cr-EDTA. The volume of distribution in microlitres of Cr-EDTA in the parenchyma was about 60% of the volume of the interstitial tissue as determined on frozen sections by morphometry, and was similar, or slightly less, in the ligated testes, compared with the unligated testes. Heating the testes to 43 degrees C for 30 min led to the expected reduction several days later in testis mass, but the volume of distribution of Cr-EDTA was no greater than that in the testes of control rats, and the ratio of Cr-EDTA space to interstitial tissue was not different, while the concentration of Cr-EDTA in the additional seminiferous tubular fluid increased only slightly as testis mass fell. These results indicate that the blood-testis barrier was only slightly less effective, if changed at all, during the period of spermatogenic disruption following local heating of the testis.

Animals↗
PubMed1988

Monoclonal antibody 123C3, identifying small cell carcinoma phenotype in lung tumours, recognizes mainly, but not exclusively, endocrine and neuron-supporting normal tissues.

Monoclonal antibody (MAb) 123C3 was raised against a membrane preparation of a small cell lung carcinoma (SCLC) specimen and its reactivity on normal tissues was tested. For the endocrine system, positive tissues included: pituitary and adrenal glands, thyrocytes and C-cells of the thyroid, the parathyroids, testis Leydig cells and pancreatic islets. In bronchioles and intestinal epithelium occasional cells, resembling Kultchitsky and enterochromaffin cells, were also positive. Epithelia like rete testis, mammary epithelium and gastric mucosa were positive in all or a significant proportion of cells. The positive cells in mammary epithelium and gastric mucosa were too numerous to represent the endocrine cells only. Neurons were usually negative or weakly positive. Their supportive cells such as glial, Schwann and ganglionic satellite cells were positive. Mesenchymal cell types, such as smooth muscle cells in most organs, cardiac muscle cells, the pia-arachnoid and ovarian stroma cells were positive, indicating that 123C3 reactivity is not confined to epithelial and neuron-supporting tissues. In Western blots of tumour specimens 123C3 recognized a 29 kDa band in reducing conditions, shifting to approximately 150 kDa in non-reducing conditions. Immunofluorescence on live tissue culture cells demonstrated presence of the antigen on the cell surface.

Animals↗
PubMed1993

Purification and characterization of rat epididymal-fluid alpha-D-mannosidase: similarities to sperm plasma-membrane alpha-D-mannosidase.

We have previously reported the occurrence and partial characterization of a novel alpha-D-mannosidase activity on rat sperm plasma membranes [Tulsiani, Skudlarek and Orgebin-Crist (1989) J. Cell Biol. 109, 1257-1267]. Here, we report the presence of a similar alpha-D-mannosidase activity in a soluble form in rat epididymal fluid. The soluble enzyme was purified nearly 500-fold with 9-12% recovery to a state approaching homogeneity using: (1) (NH4)2SO4 precipitation; (2) affinity chromatography on immobilized mannan and D-mannosamine; (3) ion-exchange (DE-52) column chromatography; (4) molecular-sieve chromatography. The enzyme was eluted from the final column (Sephacryl S-400) at an apparent molecular mass of 460 kDa. When resolved by SDS/PAGE (under denaturing conditions), the enzyme showed a major protein band (115 kDa) and few very minor bands. The polyclonal antibody raised against the major protein band was found to cross-react with the alpha-D-mannosidase activity present in epididymal fluid (soluble) and detergent-solubilized spermatozoa from the rat and mouse. This result suggested that the soluble and membrane-bound enzyme activities shared a common antigenic site(s). The antibody was used to characterize further the alpha-D-mannosidase activity(ies) present in the rat epididymal fluid and rat sperm plasma membranes. Data from these studies show that the two forms are similar in (a) subunit molecular mass, (b) substrate specificity and (c) inhibitory effect of several sugars. These similarities suggest that the soluble and membrane-bound alpha-D-mannosidase activities are isoforms. Immunoprecipitation studies after solubilization of the testis and epididymal particulate fraction from sexually immature rats show that the testis (but not the epididymis) contains the immunoreactive alpha-D-mannosidase activity. This result and the fact that spermatozoa from the rat rete testis show alpha-D-mannosidase activity indicate that the sperm enzyme is synthesized in the testis during spermatogenesis.

Animals↗
PubMed1983

The effect of age, mating and vasoligature on angiotensin I converting enzyme in rat testis and epididymis.

Angiotensin I converting enzyme was measured in testis, different sections of epididymis and vas deferens of rats with the analytical method of Piquilloud et al. In tissue specimens without a prior washout of seminal fluid the highest enzyme activity was found in the testis. The enzyme activity fell significantly towards the end of the excurrent ducts, suggesting that the enzyme is synthesized in the Sertoli cells of the testis, undergoes exocrine secretion and is partially inhibited during passage through the epididymis. This was supported by additional analyses of seminal fluid from rete testis and vas deferens. According to data obtained from various age groups, sexual stimulation due to mating and bilateral vasoligature, enzyme synthesis in the testis and enzyme inhibition in the epididymis seem to be under simultaneous (androgenic) control. Though the highest specific enzyme activity in the rat is located in the gonads, CE's enzyme substrate and the anatomical structures on which its reaction product is effective are not yet apparent.

Aging↗
PubMed1988

[Simple cysts of the testis in children. Apropos of 2 cases].

Reporting two cases of simple testicular cysts in children, the authors analyse these rare benign tumors (9 other cases in literature). The cystic dilatation first affect the rete testis, it can be partial (simple cyst) or extensive (multicystic dysplasia). The primitive perturbation would affect the mesonephrotic formations, with a defect of junction between the two different embryologic formations of the testicle and its excretor system. These tumors are revealed by a large isolated testicle, histology only makes the diagnosis. Despite their benignity, simple orchidectomy is the save treatment; enucleation is justified only when the opposite testicle is also injured.

Cysts↗
PubMed1998

Multiple testicular sampling in non-obstructive azoospermia--is it necessary?

Spermatogenesis may be focal in non-obstructive azoospermia. The present study was conducted to determine whether the performance of multiple, rather than a single testicular sample contributes to obtaining spermatozoa in amounts sufficient for fertilization and cryopreservation in non-obstructive, azoospermic patients. Furthermore, the aim was to clarify the significance of location for retrieval from the testis in such cases. Three biopsies were taken from identical locations in 55 testes of 29 men with non-obstructive azoospermia: (i) the rete testis region, ii) the midline, and (iii) the proximal region of the testis. When sperm cells were detected, they were used for intracytoplasmic sperm injection (ICSI), and the remainder were then cryopreserved in as many aliquots as possible (adjusted for ICSI procedure). Spermatozoa were found in 28 testes (50.9%) of 18 men (62.1%). In the testes from which spermatozoa were obtained, they were present in three, two or one locations in 15 (53.6%), five (17.9%) and eight (28.6%) cases respectively. The possibility of finding spermatozoa was not influenced by the location in the testis. Multiple testicular sperm extraction is recommended in cases of non-obstructive azoospermia, since it may enhance diagnostic accuracy of absolute testicular failure and increase the number of sperm cells retrieved.

Adult↗
PubMed2001

Oestrogen, its receptors and function in the male reproductive tract - a review.

Oestrogen is synthesized in the male reproductive system by at least three different cell types; Sertoli, Leydig and germ cells. Although testosterone is recognized as the primary sex steroid in man, oestrogen is produced in sizable quantities in the testis, as well as the brain and is found in extremely high concentrations in the semen of several species. The high concentration of oestrogen in rete testis fluid of the rodent is now thought to be derived from the conversion of testosterone to estradiol by P450 aromatase in germ cells of the testis and spermatozoa traversing the reproductive tract. This new major source of oestrogen would target oestrogen receptors in the male reproductive tract, in particular the efferent ductules, which contain the highest concentration of oestrogen receptor-alpha. This recent data raises new hypotheses regarding the role of oestrogen in the function of the male reproductive system. The oestrogen receptor-alpha knockout mouse was used to help define the function of oestrogen in the male. It was found that oestrogen receptor-alpha is essential for fluid reabsorption in the efferent ductules and in the absence of expression the male is infertile.

Animals↗
PubMedDate not supplied

The neural cell adhesion molecule (NCAM) provides clues to the development of testicular Leydig cells.

As previously shown, Leydig cells in culture dramatically up-regulate the expression of the neural cell adhesion molecule (NCAM) gene and express alternatively spliced forms. Because the family of NCAM adhesion molecules is known to be involved in cell migration and differentiation, we examined the potential involvement of NCAMs in Leydig cell differentiation in the developing testis. We detected NCAM-immunoreactive cells in the rat and mouse at embryonic day (ED) 13-14 in epithelia of mesonephric tubules and cell clusters between the mesonephros and testis. At about ED 17-18, strongly NCAM-immunoreactive cells were demonstrated extending from the mesonephros/mesonephric tubules into the region occupied by the forming rete testis and spreading into the testis itself. Within the testis, interstitial fetal Leydig cells, identified with an antiserum directed against P450-side-chain cleavage enzyme, were also NCAM immunoreactive, although to a lesser degree, and in part expressed NCAM-associated polysialic acid. In situ hybridization histochemistry demonstrated the presence of NCAM mRNA, mainly in the cell population corresponding to the strongly immunoreactive cells. NCAM forms with molecular weights of 140 and 180 kDa, the latter polysialylated, predominate in immunoblots of fetal testes. Because testicular development occurs along the mesonephros, from which precursor cells are thought to migrate into the developing gonad and then differentiate into the various testicular cell types, our results may suggest that the expression of NCAMs and NCAM modification are associated with cells that appear to migrate into the developing testis. Although it remains to be proven whether these cells could be precursor cells of Leydig cells, this assumption is supported by the fact that within the developing testis, NCAMs and NCAM modifications are expressed during differentiation of testicular P450-side-chain cleavage enzyme-positive Leydig cells. Thus, the adhesion molecule NCAM and its variants and modifications are expressed in the developing testis and may be of functional, "morphogenic" importance. Because Leydig cells in vitro and during fetal development express NCAMs, these molecules may prove to be a suitable specific marker for the study of Leydig cell development and differentiation.

Animals↗