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PubMed1994

hCG-induced changes in LH/CG receptor mRNA transcript levels in the testis of adult hypophysectomized, ethane dimethyl sulphonate-treated rats.

To elucidate the molecular mechanisms involved in the development of precursor cells into functional Leydig cells, effects of hCG on the expression of the luteinizing hormone (LH)/chorionic gonadotrophin (CG) receptor gene were investigated in the testis of adult hypophysectomized, ethane dimethyl sulphonate (EDS)-treated rats. The alkylating drug EDS specifically destroys Leydig cells in the adult rat testis. In hypophysectomized rats, in the absence of LH, this is not followed by the formation of new Leydig cells, leaving a testis in which Leydig cell precursors are presumed to be the only cell type that possess LH receptors. The absence of Leydig cells was confirmed by determining the gene expression of two key steroidogenic enzymes, 3 beta-hydroxysteroid dehydrogenase/isomerase (3 beta HSD) and P-450 17 alpha-hydroxylase/C17-20 lyase (P-45017 alpha) in these animals. Northern blot analysis revealed that hypophysectomy, followed by EDS treatment decreased the total amount of LH/CG receptor mRNA and drastically changed the pattern of LH/CG receptor mRNA transcripts. In the testis of intact adult rats, the expression of the LH/CG receptor gene results in multiple mRNA transcripts with molecular sizes of approximately 7.0, 4.2, 2.5, 1.8 and 1.2 kb. The most abundant species observed in the testis of adult hypophysectomized, EDS-treated rats was the 1.8 kb mRNA transcript, whereas the levels of the other mRNA transcripts were decreased. To stimulate the development of precursor cells into functional Leydig cells, hypophysectomized, EDS-treated rats were treated with high doses of hCG (100 IU) for different periods of time.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Hydroxysteroid Dehydrogenases↗
PubMed1987

High mobility group (HMG) proteins in the tammar wallaby Macropus eugenii: quantitative variations between tissues and testis-specific co-extracted proteins.

1. Tammar wallaby (Macropus eugenii, Marsupialia) proteins with similar electrophoretic mobilities to calf non-histone chromosomal proteins HMG 1, 2, 14 and 17 are perchloric acid extracted from whole tissues (liver, kidney, spleen, brain and testis) and purified liver nuclei (using PCA or 0.35 M NaCl). 2. Tammar and calf HMG 1 have similar amino acid compositions. 3. Two testis-specific basic proteins co-extracting with HMG-like proteins from both tammar and red kangaroo (Megaleia rufa) are found in whole testis, purified testis nuclei, but not epididymis. 4. Tammar HMG 2 separates into two components on both acid urea and SDS gels. The larger, more basic protein, HMG 2b, is relatively abundant in proliferating tissues (testis, spleen).

Amino Acids↗
PubMed1996

Noninvasive analysis of water movement in rat testis using deuterium magnetic resonance imaging.

To measure water movement in the testis without the effects from the blood-testis barrier, we performed in vivo deuterium magnetic resonance imaging (2H MRI) of rats administered with deuterated saline. Alcohol was injected into one testis of each animal and the other was administered with normal saline as a control. Dynamic 2H MRI was obtained at 2 T by FLASH pulse sequence (TR, 300 ms; TE, 10 ms; alpha = 90 degrees) using a surface coil (3 cm in diameter). The variation in 2H signal intensity between the two testes as a function of time after deuterated saline injection was examined every 1.1 min up to 20 min. The signal intensity in the testis receiving the alcohol treatment was lower than that in the normal control. Thus, deuterium MRI can be used to analyze functional disorders of the testis.

Animals↗
PubMed1991

Purification and characterization of recombinant human testis angiotensin-converting enzyme expressed in Chinese hamster ovary cells.

Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.

Animals↗
PubMed2006

The intertubular compartment morphometry in capybaras (Hydrochoerus hydrochaeris) testis.

The aim of the present study was to characterize the intertubule element volume density, individual and total Leydig cells volume, Leydig cell number per testis and per gram of testis, and leydigosomatic index in adult capybaras. Eight capybaras from a commercial abattoir were utilized. The intertubular compartment volume density and the Leydig cells were 45.2 and 31.13%, respectively. The individual and total Leydig cell volumes were 8.51 and 2169.41 x 10(-12) mL, respectively. The Leydig cell number per testis was 3.8 billion and the Leydig cell number per gram of testis was 126 million. The leydigosomatic index was 0.037%. In conclusion, this study shows that capybaras have one of the greatest individual and total Leydig cell volume and Leydig cell volume density, and that the Leydig cell number per gram of testis is at least double the mean for mammals previously investigated in its order.

Abattoirs↗
PubMed2005

Germ cell transplantation and testis tissue xenografting in domestic animals.

Transplantation of germ cells from fertile donor mice to the testes of infertile recipient mice results in donor-derived spermatogenesis and transmission of the donor's genetic material to the offspring of recipient animals. Germ cell transplantation provides a bioassay to study the biology of male germ line stem cells, develop systems to isolate and culture spermatogonial stem cells, examine defects in spermatogenesis and treat male infertility. Although most widely studied in rodents, germ cell transplantation has been applied to larger mammals. In domestic animals including pigs, goats and cattle, as well as in primates, germ cells can be transplanted to a recipient testis by ultrasonographic-guided cannulation of the rete testis. Germ cell transplantation was successful between unrelated, immuno-competent pigs and goats, whereas transplantation in rodents requires syngeneic or immuno-compromised recipients. Genetic manipulation of isolated germ line stem cells and subsequent transplantation will result in the production of transgenic sperm. Transgenesis through the male germ line has tremendous potential in domestic animal species where embryonic stem cell technology is not available and current options to generate transgenic animals are inefficient. As an alternative to transplantation of isolated germ cells to a recipient testis, ectopic grafting of testis tissue from diverse mammalian donor species, including horses and primates, into a mouse host represents a novel possibility to study spermatogenesis, to investigate the effects of drugs with the potential to enhance or suppress male fertility, and to produce fertile sperm from immature donors. Therefore, transplantation of germ cells or xenografting of testis tissue are uniquely valuable approaches for the study, preservation and manipulation of male fertility in domestic animals.

Animals↗
PubMed2006

Anti-estrogen ICI 182.780 and anti-androgen flutamide induce tyrosine phosphorylation of cortactin in the ectoplasmic specialization between the Sertoli cell and spermatids in the mouse testis.

Our previous study revealed that the ectoplasmic specialization (ES) was deleted by the treatment of anti-estrogen, ICI 182.780 (ICI), and anti-androgen, flutamide (FLUT) in mouse testis. Also, expression of cortactin, an F-actin-binding protein, was decreased by the treatment of FLUT in mouse testis. Cortactin has been suggested to promote actin polymerizer at the ES in the testis, and also actin depolymerization is induced by tyrosine phosphorylation of cortactin. The present study revealed that exogenous treatment of ICI and FLUT caused the deletion of the cortactin in the apical ES and the increase of tyrosine phosphorylated cortactin in mouse testis. These results suggest that the sex hormone antagonists', ICI and FLUT, induced actin depolymerization and tyrosine phosphorylation of cortactin in the mouse testis. Also, the present study may be a key to elucidate the adverse affect exogenous compounds that affect spermiation.

Androgen Antagonists↗
PubMed2005

Cyproterone acetate affects protamine gene expression in the testis of adult male rat.

The temporal effects of oral administration of cyproterone acetate (CPA), a progestational androgen receptor blocker, were studied on the fertility of adult male rat sires, at a dose of 20 mg kg-1 day-1 after 15 days of gavage. The treatment reduced the fertility and weights of accessory sex glands, without altering the serum levels of luteinizing hormone, follicle-stimulating hormone (FSH) and testosterone (T). Sperm counts were significantly reduced after treatment. Several changes were evident in caput epididymal sperm chromatin in treated rats. The in vitro decondensation rates of sperm chromatin and total fluorescent acridine orange (AO) dye uptake were enhanced. The fluorescent AO dye uptake by the double- and single-stranded sperm chromatin increased. The uptake of thiol-specific monobromobimane fluorescent dye by sperm chromatin was significantly reduced. Sperm of treated rats exhibited hypoprotamination. Protamine levels in the testis were significantly reduced after treatment. Androgen-binding protein (ABP) expression was significantly reduced in testis after treatment. A slight but significant increase was observed in cyclic AMP immunoexpression in testis after treatment. The expression and levels of transition proteins 1 (TP1) and 2 (TP2) as well as cyclic AMP response element modulator protein-tau were maintained at control levels in the testis of treated rats. The present study reports that androgen receptor occupation by CPA preferentially reduces the levels of spermatidal protamine in testis and spermatozoa involved in nuclear chromatin condensation. It is inferred that ABP could be mediating the effects of T in modulating the sequential expression of TPs and protamines during nuclear chromatin condensation. It is likely that indirect effects of T involve its aromatization in spermatids.

Androgen Antagonists↗
PubMed2006

Expression of a fluorescent recombinant form of sperm protein phospholipase C zeta in mouse epididymal sperm by in vivo gene transfer into the testis.

OBJECTIVE: To use in vivo gene transfer into the testis by electroporation to express a fluorescent recombinant form of a testis-specific gene in the mature epididymal sperm of mice and thus study the pattern of gene localization. DESIGN: Controlled animal study. SETTING: Research laboratory at the University of Oxford. ANIMAL(S): Four- to 6-week-old male mice. INTERVENTION(S): Phospholipase C zeta (PLCzeta), the putative mammalian egg activation factor, was fused to enhanced yellow fluorescent protein (EYFP), and in vivo gene transfer by electroporation was used to introduce this transgene (PLCzeta-EYFP) into mouse testis. Transgene expression in testis and sperm were analyzed at 20 and 40 days after electroporation. MAIN OUTCOME MEASURE(S): Transgene expression in testis and epididymal sperm was analyzed by fluorescence microscopy and an excitation light source suitable for EYFP. RESULT(S): Phospholipase C zeta-EYFP was successfully expressed in epididymal sperm when analyzed 40 days after gene transfer and was localized to the head and midpiece regions. CONCLUSION(S): Our results provide the first demonstration that in vivo gene transfer can be used to study the localization of proteins in mature sperm and that this represents a powerful new technique for studying male infertility and gene function in sperm.

Animals↗
PubMed2004

Testis-specific transcriptional control.

In the testis, tissue-specific transcription is essential for proper expression of the genes that are required for the reproduction of the organism. Many testis-specific genes are required for mitotic proliferation of spermatogonia, spermatocytes undergoing genetic recombination and meiotic divisions, and differentiation of haploid spermatids. In this article we describe some of the genes that are transcribed in male germinal cells and in non-germinal testis cells. Because significant progress has been made in examination of promoter elements and their cognate transcription factors that are involved in controlling transcription of the testis-specific linker histone H1t gene in primary spermatocytes, this work will be reviewed in greater detail. The gene is transcriptionally active in spermatocytes and repressed in all other germinal and non-germinal cell types and, therefore, it serves as a model for study of regulatory mechanisms involved in testis-specific transcription.

Animals↗
PubMed2005

Tissue microcircumstances for leukocytic infiltration into the testis and epididymis in mice.

Spermatozoa do not appear in the seminiferous epithelium until puberty, when immune tolerance has already been established. Therefore, they contain various autoimmunogenic materials which are recognized as foreign by the self immune system. However, the testis and epididymis are known as immunologically privileged organs. In particular, the blood-testis barrier (BTB) formed by Sertoli cells and the blood-epididymal barrier formed by epididymal epithelial cells protect autoimmunogeneic spermatozoa from attack by the self immune system. The immune privileged circumstances in the testis and epididymis have been demonstrated by many studies to involve a local transplantation system. We review here the immune privileged status of these organs from the viewpoint of induction of inflammatory cell responses in mice. The testicular interstitium in mice is resistant to vasculitis, lymphangitis, spermatic granuloma and polymorphonuclear cell infiltration: however, the epididymal interstitium is vulnerable to them. Therefore, the testicular tissue outside BTB is also protected from inflammatory cell infiltration, although many resident macrophages are normally present in the testis. In sharp contrast, subcutaneous injection of viable syngeneic testicular germ cells (TGC) alone induces autoimmune orchitis with no involvement of the epididymitis in mice. In the testes of TGC-immunized animals, severe lymphocytic infiltration with aspermatogenesis was seen in spite of no use of adjuvants. Unexpectedly, injections of viable epididymal spermatozoa (ES) did not evoke any autoimmune inflammation in the epididymides. Therefore, the testis rather than the epididymis may easily become an unprivileged organ as to autoimmunity under some special conditions.

Animals↗
PubMed2006

Benzo[a]pyrene cytotoxicity in right whale (Eubalaena glacialis) skin, testis and lung cell lines.

The North Atlantic right whale (NARW) is one of the most endangered great whales. The NARW population consists of only about 300 individuals and is reproducing at an insufficient rate. There is growing concern about the potential effects of environmental contaminants on the reproductive and overall health of NARW. High contaminant burdens can accumulate in tissues of great whales but toxicological studies of their effects are limited due to legal, logistical and ethical restrictions and specific in vitro models are critically needed. Cell lines from NARW skin and internal organs were previously created in our laboratory. In this study, skin, testis and lung primary fibroblast cell lines were exposed to benzo[a]pyrene (BP) as part of a multi-chemical toxicity testing project in NARW. Cells were exposed for 24-72 h to 10 nM-10 microM BP dissolved in dimethylsulfoxide. Cytotoxicity was measured with a clonogenic assay using standard methods. Some cytotoxicity was observed after 24 h, the highest concentration (10 microM BP) resulting in 77, 74 and 51 percent relative survival in testis, skin and lung cells, respectively, and indicating a higher cytotoxicity in the lung (p < 0.05). After 48 and 72-h exposure, 10 microM BP resulted in 24 and 3, 74 and 27, and 42 and 23 percent relative survival in testis, skin and lung cells, respectively. Cytotoxicity significantly increased with exposure time in all three tissues (p < 0.05 for skin and p < 0.01 for lung and testis), suggesting metabolic activation of BP in the three organs. Fibroblast cytotoxicity observed in the testis was higher than that observed either in the skin or lung after 48 h (p < 0.01) and was close to 100% after 72 h, warranting further investigation of the potential effects of PAHs on reproductive health.

Animals↗
PubMed2003

Human testis specific protein: a new member of aldo-keto reductase superfamily.

Human testis specific protein, HTSP, was identified initially by the search of the Expressed Sequence Tag database, followed by the screening of human testis cDNA library. Among various organs examined, the HTSP transcripts were detected only in the testis, not in other reproductive organs such as vas deferens and prostate. No cross-hybridizing signal was detected in the testis of mouse or rat, indicating that this gene is specifically expressed in the human testis. We isolated four isoforms, HTSP1, 2, 3 and 4. Screening of the high throughput genomic sequence database indicated the localization of the HTSP gene in chromosome 10. Thus, HTSP isoforms were generated by alternative splicing of a single gene. HTSP4, the longest gene product, was composed of 307 amino acids and shared 56% identity to mouse vas deferens protein as well as human aldose reductase in amino acid levels. Bacterially expressed recombinant HTSP protein showed small but significant activity towards 9,10-phenanthrenequinone among the putative substrates so far tested. Accordingly, HTSP is a new member of the aldo-keto reductase superfamily with as yet unidentified function.

Alcohol Oxidoreductases↗
PubMed2003

Ethane 1,2-dimethane sulphonate is a useful tool for studying cell-to-cell interactions in the testis of the frog, Rana esculenta.

Ethane 1,2-dimethane sulphonate (EDS), a toxin which specifically destroys Leydig cells (LC), has been used to study cellular interactions in the testis of the frog Rana esculenta. Animals received three consecutive EDS injections and were sacrificed on day 4, 8, and 28 from the first injection. No significant morphological differences were observed between present observation and that obtained, in a previous experiment, after four consecutive EDS injections. In fact, on day 4, in the germinal tubules adjacent to apparently normal LC, Sertoli cells surrounding primary spermatogonia (I SPG) show heterochromatic nuclei and loss of cellular adhesion. Interestingly, I SPG surrounded by the heterochromatic Sertoli cells present grossly swollen mitochondria with ballooned cristae. On day 8, sometimes in the interstitium many LC appear strongly damaged and the germinal tubules appear disorganized; the only cell type still distinguishable is the I SPG. On day 28 from the first EDS injection a new population of LC reappear in the interstitium and spermatogenesis normalizes. These data confirm the close relationship between the interstitial and the geminal compartments. Immunocytochemical data obtained using a polyclonal antibody anticonnexin-43 (Cx-43, the most abundant Cx found in mammalian testis) demonstrate the presence of Cx-43 in the frog testis. In particular, Cx-43 is present between LC in the interstitium, between Sertoli and germ cells in the cysts and between Sertoli cells and I SPG. Cx-43 immunopositivity sharply decreases on day 4 from the first EDS injection simultaneously with the loss of cellular adhesion between Sertoli and germ cells. On day 8 and 28 from the first EDS injection Cx-43, immunopositivity is restored and, this data is also supported by Western blot analysis. Our data provide, for the first time, evidence that Cx-43 protein is present in the frog testis and confirm that EDS is a useful tool for studying cellular communication at the paracrine pathway or through direct contact depending on the gap junctional pathway in R. esculenta testis

Animals↗
PubMed1980

Results of the use of autotransplantation of the intraabdominal testis using microsurgical vascular anastomosis.

This study indicates that where facilities are available, the use of autotransplantation of the intraabdominal testis with microsurgical anastomosis to vessels of the groin is an acceptable, and possibly the best, alternative to orchidectomy for the intraabdominal testis. It is certainly justifiable in the case of the bilateral intraabdominal testis but in the case of the unilateral intraabdominal testis with a normally descended and apparently normal testis in the opposite hemiscrotum, the incresed incidence of neoplasia in intraabdominal testes should be taken into account in the decision on the method of treatment.

Adolescent↗
PubMed2002

Cystic ectasia of the rete testis: clinical and radiographic features.

PURPOSE: Cystic ectasia of the rete testis is a rare condition that may be incidentally noted on scrotal ultrasonography. This benign condition has a typical appearance of a collection of small anechoic structures in the confluence of the mediastinum testis. The main significance of this condition is that it must be differentiated from testicular neoplasm. We reviewed the experience with this condition at our institution. MATERIALS AND METHODS: A retrospective review was performed to identify all sonograms showing ectatic rete testis performed from 1998 through February 2002. A departmental database was used to identify all scrotal sonograms from this period showing ectasia of the rete testis and clinical correlation was done. These examinations were then reviewed by a single radiologist. RESULTS: We identified 13 cases in the last 4 years. Ultrasound was most commonly performed for a testicular or scrotal mass, or pain. Median patient age was 65 years. All except 1 patient had an underlying condition, including vasectomy, epididymal cyst/spermatocele or inguinal hernia repair, that could cause epididymal or efferent duct obstruction. No patient had a solid testicular mass. CONCLUSIONS: Based on clinical and sonographic criteria the diagnosis of cystic ectasia of the rete testis can be made without histological confirmation. Identifying this entity and its associated conditions avoids the need for biopsy or orchiectomy.

Adult↗
PubMed1992

Evidence for a non-androgenic role of testis and epididymis in androgen-supported growth of the rat ventral prostate.

A widely held view is that the role of testis in prostatic growth is through its ability to secrete androgen. Our earlier observation suggested a non-androgenic role for the testis, and perhaps the epididymis, in promoting growth of the ventral prostate in rats. The present study was conducted to evaluate the separate role of the testis and the epididymis in this phenomenon. In the first study, increasing quantities of silastic tubing filled with crystalline testosterone were implanted into adult Sprague-Dawley rats at the time of bilateral epididymo-orchiectomy or sham-operation. Twenty-eight days later, growth of the ventral prostate, as determined by fresh weight, DNA, and protein content, was significantly greater in sham-operated rats than in those receiving combined epididymo-orchiectomy, confirming our previous observation using dihydrotestosterone. In the second and third studies, rats were subjected to selective surgical procedures to evaluate the independent role of the testis and the epididymis. At the same time, 12 cm silastic tubing filled with testosterone or dihydrotestosterone were implanted subcutaneously into each of these animals for 28 days. Results indicated that the ventral prostate was significantly smaller in rats receiving the combined epididymo-orchiectomy than that of sham-operated controls. Simple orchiectomy or simple epididymectomy resulted in an increased weight of the ventral prostate between the two values obtained from the above two groups. Ligation of either the efferent duct or the vas deferens yielded ventral prostatic weights comparable to the androgen-treated, sham-operated controls. These results indicated that in order to achieve a maximal effect on androgen-supported growth of the ventral prostate, the presence of both the testis and the epididymis is required.

Androgens↗
PubMed1992

Microsurgical inguinal varicocelectomy with delivery of the testis: an artery and lymphatic sparing technique.

Conventional techniques of varicocele repair are associated with substantial risks of hydrocele formation, ligation of the testicular artery, and varicocele recurrence. We describe a microsurgical technique of varicocelectomy that significantly lowers the incidence of these complications. The testicle is delivered through a 2 to 3 cm. inguinal incision, and all external spermatic and gubernacular veins are ligated. The testis is returned to the scrotum and the spermatic cord is dissected under the operating microscope. The testicular artery and lymphatics are identified and preserved. All internal spermatic veins are doubly ligated with small hemoclips or 4-zero silk and divided. The vas deferens and its vessels are preserved. Initially, we performed 33 conventional inguinal varicocelectomies in 24 men without delivery of the testis or use of a microscope. Postoperatively, 3 unilateral hydroceles (9%) and 3 unilateral recurrences (9%) were detected. For the next 12 cases 2.5x loupes were used resulting in no hydroceles but another recurrence (8%). We then performed 640 varicocelectomies in 429 men using the microsurgical technique with delivery of the testis. Among 382 men available for followup examination from 6 months to 7 years postoperatively no hydroceles and no cases of testicular atrophy were found. A total of 4 unilateral recurrent varicoceles (0.6%) was identified. The differences between the techniques in the incidence of hydrocele formation and varicocele recurrence are highly significant (p < 0.001). No wound infections occurred in any men. Four scrotal hematomas (0.6%), 1 of which required surgical drainage, occurred in the group with microsurgical ligation and delivery of the testis compared to none with the conventional technique. Preoperative and postoperative semen analyses (mean 3.57 analyses per patient) were obtained on 271 men. The changes in sperm count x 10(6) cc (36.9 to 46.8, p < 0.001), per cent motility (39.6 to 45.7%, p < 0.001) and per cent normal forms (48.4 to 52.10%, p < 0.001) were highly significant. The pregnancy rate was 152 of 357 couples (43%) followed for a minimum of 6 months postoperatively. Delivery of the testis through a small inguinal incision provides direct visual access to all possible avenues of testicular venous drainage. The operating microscope allows identification of the testicular artery, lymphatics and small venous channels. This minimally invasive, outpatient technique results in a significant decrease in the incidence of hydrocele formation, testicular artery injury and varicocele recurrence.

Adolescent↗