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PubMed2000

Changes in the testis interstitium of Sprague Dawley rats from birth to sexual maturity.

Changes in the rat testis interstitium from birth to adulthood were studied using Sprague Dawley rats of 1, 7, 14, 21, 28, 40, 60, and 90 days of age. Our objectives were 1) to understand the fate of the fetal Leydig cells (FLC) in the postnatal rat testis, 2) to determine the volume changes in testicular interstitial components and testicular steroidogenic capacity in vitro with age, 3) to differentially quantify FLC, adult Leydig cells (ALC), and different connective tissue cell types by number and average volume, and 4) to investigate the relationship between mesenchymal and ALC numbers during testicular development. FLC were present in rat testes from birth to 90 days, and they were the only steroidogenic cells in the testis interstitium at Days 1 and 7. Except for FLC, all other interstitial cell numbers and volumes increased from birth to 90 days. The average volume of an FLC and the absolute volume of FLC per testis were similar at all ages except at Day 21, when lower values were observed for both parameters. FLC number per testis remained constant from birth through 90 days. The observations suggested that the significance of FLC in the neonatal-prepubertal rat testis is to produce testosterone to activate the hypothalamo-hypophyseal-testicular axis for the continued development of the male reproductive system. ALC were the abundant Leydig cell type by number and absolute volume per testis from Day 14 onwards. The absolute numbers of ALC and mesenchymal cells per testis increased linearly from birth to 90 days, with a slope ratio of 2:1, respectively, indicating that the rate of production of Leydig cells is 2-fold greater than that of mesenchymal cells in the postnatal rat testis through 90 days. In addition, this study showed that the mesenchymal cells are an active cell population during testis development and that their numbers do not decrease but increase with Leydig cell differentiation and testicular growth up to sexual maturity (90 days).

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed2001

In vitro production of haploid germ cells from fresh or frozen-thawed testicular cells of neonatal bulls.

Improved methods for culturing spermatogenic cells will facilitate the study of spermatogenesis, treatment of male factor infertility, and genetic modification of the male germ line. The objective of this study was to develop a procedure for achieving male germ cell progression through meiosis in vitro. Testes from 3-day-old bulls were decapsulated and seminiferous tubules were dissociated enzymatically to recover Sertoli and germ cells. Dissociated cells were reaggregated by phytohemagglutinin and encapsulated by calcium alginate, then cultured for up to 14 wk in modified Dulbecco modified Eagle medium/F12 (32 degrees C, 5% CO(2) in air). At 2, 5, and 10 wk, cultured cells were examined and evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analysis for protamine-2 (PRM-2) and transition protein-1 (TP-1) mRNA, expressed specifically in round spermatids. Ploidy was characterized by flow cytometric analysis of DNA content of cultured cells. Only Sertoli cells and gonocytes were observed in seminiferous tubules of 3-day-old testes. By 10 wk of culture, small spherical cells (7-10 microm) were apparent at the margin of cell associations in culture. Following RT-PCR and Northern blot analysis, specific bands corresponding to PRM-2 and TP-1 were detected only in adult testis RNA or after 10 wk of culture. Based on flow cytometry, a haploid population of cells appeared in vitro that was not in 3-day-old bull testis. The novel culture system developed in this study is the first to promote differentiation of gonocytes to presumptive spermatids in vitro based on the expression of spermatid-specific genes.

Animals↗
PubMed1989

Selective induction of heme oxygenase-1 isozyme in rat testis by human chorionic gonadotropin.

A radioimmunoassay was developed to assess the response of testicular HO-1 to agents known to increase the microsomal heme oxygenase activity. Treatment of rats with human chorionic gonadotropin (hCG) increased the microsomal heme oxygenase activity in rat testis. The following data suggest that the increase was specific to the HO-1 isozyme: (a) The elution profile of heme oxygenase activity from a DEAE-Sephacel column showed an increase in the HO-1 peak, but not in the HO-2 peak, (b) the Western immunoblot of the testis microsomes showed an increase in HO-1 protein, and (c) the amount of HO-1 protein that was present in the microsomes, when measured by radioimmunoassay, was doubled. Using radioimmunoassay, it was shown that other agents known to increase the testicular heme oxygenase, sodium arsenate and sodium arsenite, also increased the microsomal content of HO-1. An inhibitor of the testicular microsomal heme oxygenase activity, cadmium, also increased the microsomal HO-1 protein. The findings suggest that inducibility of HO-1 extends to tissues other than the liver, in this instance, the testis, and further support the possibility that HO-1 is the only inducible form of heme oxygenase.

Animals↗
PubMed1985

Stage-dependent changes in steroidogenic enzymes and estrogen receptors during spermatogenesis in the testis of the dogfish, Squalus acanthias.

In the spiny dogfish (Squalus acanthias), germ cells and adjacent steroidogenic elements are topographically segregated within the testis according to stage of development. In the experiments reported here, we have taken advantage of this favorable anatomical arrangement to demonstrate stage-specific variations in steroidogenic enzymes and estrogen receptor number. The testes of Squalus collected in July-November were sectioned transversely and further subdivided into three zones as follows: I) germinal bed plus immature lobules with spermatogonia; II) lobules with primary or secondary spermatocytes; III) lobules with spermatids or mature spermatozoa. The morphology of these zones was verified by light microscopy and, in a separate study, by electron microscopy. Through the course of spermatogenesis, Sertoli cells increased dramatically in size and in the abundance of steroidogenic organelles. By contrast, interstitial tissue was sparse in all stages of development, and only relatively undifferentiated Leydig-like cells were present. Microsomes prepared from each zone were incubated with [3H] progesterone, [3H]17 alpha-hydroxyprogesterone, or [3H]androstenedione to evaluate androgen and estrogen biosynthetic potentials. Based on product formation, 17 alpha-hydroxylase and C-17,20-lyase activities increased progressively from less mature to more mature regions (zone III greater than II greater than I), whereas aromatase was greatest in regions undergoing meiosis or early spermiogenesis (zone II). These enzymes were not detected in semen, although C21 substrates were converted to unidentified polar metabolites in high yield. Estrogen receptors were concentrated in immature zones (zone I greater than II greater than III), and the percentage of occupied receptors revealed the same distribution. Semen and epigonal tissues were receptor negative. We conclude that Sertoli cells are responsible for steroidogenesis in Squalus testis and that hormone production is keyed to the spermatogenic cycle. The data are consistent with an important role for androgens during spermatid maturation and/or after sperm release, but reveal that estrogen actions are expressed primarily during early spermatogenic stages. This report demonstrates the usefulness of unconventional animal models for obtaining new information of general relevance.

17-alpha-Hydroxyprogesterone↗
PubMed1995

[Idiopathic myelofibrosis with extramedullary hematopoiesis foci in the skin and testicles. Report of a case].

Idiopathic myelofibrosis (IMF) is a clonal chronic myeloproliferative syndrome characterized by the proliferation of the three haemopoietic series and the marrow connective tissue and by the development of extramedullary haemopoiesis in the liver, spleen and lymph nodes. Cutaneous extramedullary haemopoiesis is an uncommon event and we could not find any reported cases of testicular involvement in this disease. We report the case of a 28 year-old male with diagnosis of idiopathic myelofibrosis in November 1988. During the course of the disease, three years later, he developed a tumor on his right testis. Histologic examination showed extramedullary haemopoiesis with cells of the myeloid, erythroid and megakaryocyte series, in the interstice. Eight months later, numerous red-purple papules and nodules developed on the patients's trunk. The biopsy of a skin lesion revealed an infiltration of the dermis by myeloid, erythroid cells and few megakaryocytes. The patient's clinical condition worsened, and he died in February 1993 following progressive deterioration of the general condition. We describe a case of IFM with extramedullary hemopoiesis involving the skin and the testis pointing out the rarity of these localization.

Adult↗
PubMed1987

Seminoma of testis: the value of aggressive therapy, and risk of late bilateral involvement.

The results of aggressive therapy for seminoma of the testis have improved dramatically during the past decade. A patient who eight months after orchidectomy had a pulmonary metastasis excised and who nine years later developed a seminoma in the contralateral testis is described. One consequence of the much longer survival time now attainable is that an increasing number of cases with metachronous testicular seminomas may be encountered in the future.

Adult↗
PubMed1998

Examining the renin-angiotensin system one hundred years after its discovery.

This article reviews the biology of angiotensin converting enzyme (ACE). There are two ACE isozyme, somatic ACE (made by tissues such as the lung and kidney) and testis ACE (produced only by developing male germ cells). Mice lacking all ACE expression were prepared using homologous recombination of embryonic stem cells. These animals have profoundly low blood pressures, reduced male fertility and a renal lesion characterized by under development of the renal medulla and papilla. A second line of mice was made in which ACE activity is found in the plasma but is absent from all tissues such as lung. These animals have a phenotype very similar to mice lacking all ACE with the exception of the renal lesion which is much less pronounced. This second line of mice strongly suggests that it is tissue-bound ACE which is critical in the proper functioning of the renin-angiotensin system.

Animals↗
PubMed2004

Effects of 4-tert-pentylphenol on the gene expression of P450 11beta-hydroxylase in the gonad of medaka (Oryzias latipes).

Alkylphenols including 4-tert-pentylphenol (4-PP) have been shown to alter sexual differentiation in fish due to their estrogenic properties. Medaka (Oryzias latipes) is so sensitive to these substances because morphological sex reversal and testis-ova induction are well developed in the exposed males. However, little work has been done to characterize the molecular effects of estrogenic substances on the morphological and gonadal feminization in male fish. Cytochrome P450 11beta-hydroxylase (P450(11beta)) is a key steroidogenic enzyme in production of 11-ketotestosterone which is the predominant androgen in male fish. In this study, we cloned a cDNA encoding medaka testicular P450(11beta), and then investigated the gene expression of P450(11beta) in the testes of genetically male medaka exposed to 4-PP. The cDNA contains 1740 nucleotides that encode a protein of 543 amino acids, which shares 68.9% and 73.4% homology with testicular P450(11beta)s from Japanese eel (Anguilla japonica) and rainbow trout (Oncorhynchus mykiss), respectively. HeLa cells transfected with an expression vector containing the open reading frame of medaka P450(11beta) cDNA showed 11beta-hydroxylating activity in the presence of exogenous testosterone. Analysis of tissue distribution by RT-PCR showed great abundance of P450(11beta) mRNA in testis. In the partial life-cycle exposure with 4-PP, morphologically sex-reversal was observed in XY medaka exposed to 4-PP concentrations of > or =238 microg/L. Furthermore, exposure to 4-PP completely inhibited P450(11beta) mRNA expression in the gonads of sex-reversed XY fish at 60-day posthatch. These results suggest that xeno-estrogen 4-PP may have inhibitory effects on the synthesis of testicular 11-oxygenated androgens through downregulation of P450(11beta) expression in the genetically male fish.

Amino Acid Sequence↗
PubMed2005

[Ultrastructure of the testes and spermatogenesis in the mite Anystis baccarum].

The epithelial lining of testes in Anystis baccarum is glandular and produces a secretory product necessary to form spermatophores. The main stages of spermatogenesis occur in the lumen of the testis in groups of synchronously developing sister cells. Spermatogonia and late spermatids are encircled by glandular cells. Reorganization of developing spermatids is typical of the trombidiform mites and includes formation of the acrosomal complex, cytoplasm elimination, disappearance of the nuclear envelope and formation of invaginations of plasmalemma. The chromatin material condensation is not followed by the entire chromatin body formation. In mature spermatoza, dense chromatin strands (80b nm in diameter) lie along the cell in the peripheral layer of the cytoplasm. Mature spermatozoa lack axonema or any protrusions. A layer of microtubules, visible underneath the outer membrane, may serve for sperm movement in the female genital duct. The acrosomal complex consists of acromal granule, acrosomal filament and subacrosomal substance. This, as well as two aggregates of typical mitochondria, looks plesiomorphic.

Animals↗
PubMed2000

Developmental toxicity of the HIV-protease inhibitor indinavir in rats.

BACKGROUND: Indinavir is an antiviral agent used for the treatment of HIV infection. We studied its developmental toxicity in rats. METHODS: Pregnant animals were treated orally with 500 mg indinavir/kg body weight (bw) from day 6 to 15 of gestation (once daily) or from day 9 to 11 (twice daily). Fetuses were evaluated for external and skeletal anomalies on day 21 of gestation. In addition, 19 rats were treated from day 9 of gestation to day 24 postnatally with 500 mg indinavir/kg bw once daily; a control group of 17 rats was treated with the vehicle accordingly. Developmental landmarks were recorded. Sixteen offspring each were studied on postnatal days 7, 14, 21, and 35 for hepatic enzyme activity. Liver tissue was examined by electron microscopy. RESULTS: Fetal examination on day 21 of pregnancy showed no treatment-related effects on number, weight, and viability of the fetuses; however, an increased incidence was noted in the supernumerary ribs and variations of the vertebral ossification centers in both indinavir-treated groups. Postnatal evaluation showed delayed fur development, eye opening, and descensus testis. The most striking finding was unilateral anophthalmia, observed in 7 pups (3%) from 2 out of 19 litters exposed to indinavir, but not in controls. Only minor changes in hepatic monooxygenase activities occurred in dams. Electron microscopy of liver samples showed hepatocellular inclusions of lipids and myelin figure-like structures in maternal livers and infiltration with granulocytes in offspring livers. CONCLUSIONS: Further studies on reproductive toxicity, including combinations of three or more antiretroviral agents as used therapeutically, are needed to determine the hazards of such a treatment.

Abnormalities, Drug-Induced↗
PubMed2005

Modulation of the expression and transactivation of androgen receptor by the basic helix-loop-helix transcription factor Pod-1 through recruitment of histone deacetylase 1.

Androgen receptor (AR) is important in male sexual differentiation and testicular function. Here, we demonstrate the regulation of AR expression and its transactivation by the basic helix-loop-helix (bHLH) transcription factor Pod-1, the expression of which in postnatal testis reciprocally coincides with the expression of AR. Pod-1 represses the promoter activity of AR, possibly through its E-box. An AR promoter region of 169 bp, which harbors one canonical E-box, is sufficient for the Pod-1-repression and bound by purified Pod-1 proteins. Pod-1 also suppresses the transactivation of AR. Transient transfection analyses of mammalian cells show that Pod-1 represses AR transactivation in a dose-dependent manner. Furthermore, yeast two-hybrid, glutathione-S-transferase-pull-down, and co-immunoprecipitation analyses reveal that Pod-1 directly associates with AR through its N-terminal region and through the DNA binding-hinge domain of AR. Interestingly, Pod-1 recruits histone deacetylase (HDAC)-1 to inhibit both promoter activity and transactivation of AR. Overexpression of HDAC1 further inhibits the Pod-1-mediated repressions and Pod-1 directly interacts with HDAC1. Furthermore, chromatin immunoprecipitation assay reveals that HDAC1 is recruited with Pod-1 to the endogenous AR promoter and the androgen-regulated Pem promoter. Taken together, these results suggest that Pod-1, which controls AR transcription and function, may play an important role in the development and function of the testis.

Animals↗
PubMed1990

Changes in the concentration and size of testicular macrophages during development.

Structural and functional interactions exist between Leydig cells and testicular macrophages of adult rats. Since the function of Leydig cells changes during critical periods of development and postnatal maturation, it is possible that macrophages are in part involved in regulating this process. As a first step towards gaining an understanding of the development of this paracrine phenomenon, I have undertaken a series of studies designed to determine when macrophages first become identifiable in the fetal tests and to determine whether the concentration or size of macrophages changes during important stages of testicular maturation. Macrophages were identified immunohistochemically in frozen sections of testis from rats at various prenatal and postnatal ages using commercially available monoclonal antibodies to proteins specific to rat macrophages. It was found that macrophages positive for these antigens were found only within the interstitial compartment and were commonly associated with clusters of presumptive Leydig cells that were negative for these antigens. Macrophages were first identifiable in the testis at Day 19 of fetal development. The number of macrophages/unit area of interstitium increased 15-fold between Day 20 of gestation and Day 47 postpartum. The cross-sectional area of the macrophages increased 1.7-fold between Days 13 and 47 postpartum. These results demonstrate that the number and size of testicular macrophages changes with age, suggesting a role for these cells during important times of testicular development and maturation.

Aging↗
PubMed1996

Current management of the undescended testis.

True undescended testes are unilateral in approximately 80% of cases, are rarely corrected by human chorionic gonadotropin (hCG), and should be treated by orchiopexy before the patient reaches the age of 3 years to permit optimal tubular development and sperm function. A cryptorchid testis does not mature normally after the age of 2 years and may produce adverse effects on the contralateral descended testis. The higher a cryptorchid testis resides above the scrotum, the more dysgenetic the morphology is likely to be. Hypoplastic cryptorchid testes should be removed early, and high-positioned testes that have not been surgically placed into the scrotum before midadolescence generally should be removed.

Adolescent↗
PubMedDate not supplied

Testicular toxicity of boric acid (BA): relationship of dose to lesion development and recovery in the F344 rat.

High-dose boric acid (BA) produces testicular lesions in adult rats, characterized by inhibited spermiation followed by atrophy. The present study addressed whether inhibited spermiation can be separated from atrophy based on dose, compared testis boron (B) dosimetry to lesion development, determined how inhibited spermiation was reflected by common reproductive endpoints, and examined reversibility of the testicular lesions. Rats were fed 3000, 4500, 6000, or 9000 ppm BA for up to 9 weeks and examined. Recovery was assessed for up to 32 weeks post treatment. Inhibited spermiation could be separated from atrophy based on dose (inhibited spermiation: 3000/4500 ppm; atrophy: 6000/9000 ppm), with each lesion aspect expressed at different threshold testis B concentrations (inhibited spermiation: 5.6 micrograms B/g and atrophy: 11.9 micrograms B/g) with no B accumulation during the 9-week exposure. These data suggest that separate mechanisms may be operating for these lesion aspects based on testis B concentration and that B dose rate was important for testicular toxicity. Inhibited spermiation was most reliably reflected by informed testicular histology, with the more severe cases decreasing epididymal sperm count to levels that could affect fertility. After treatment, serum and testis B levels in all dose groups rapidly fell to background levels at the earliest time points evaluated (7 days and 8 weeks posttreatment, respectively). The severely inhibited spermiation at 4500 ppm was resolved by 16 weeks posttreatment, but areas of focal atrophy were detected that did not recover posttreatment. Also, no signs of recovery from atrophy were observed (6000 and 9000 ppm). Atrophic tubules contained a normal complement of spermatogonia (2.6 to 2.9 germ cells/100 Sertoli cells), with occasional dividing and degenerating germ cells. Elevations in serum FSH and LH levels suggested an intact hormonal response to the atrophy. In summary, 1) the different aspects of the BA-induced testicular lesion can be separated using different doses, 2) inhibited spermiation does not necessarily proceed to atrophy, and 3) there is no recovery from the atrophy despite the absence of testis B after treatment. The ability to separate inhibited spermiation from atrophy based on dose and testis B dosimetry will be useful in evaluating possible mechanisms. Furthermore, the presence of dividing spermatogonia during long-term BA-induced atrophy suggests that this model should be useful for identifying critical components involved in the reinitiation of spermatogenesis.

Animals↗
PubMed1994

Requirement for testicular macrophages in Leydig cell proliferation and differentiation during prepubertal development in rats.

Testicular macrophages in rats were selectively depleted by an intratesticular injection of liposomes containing dichloromethylene diphosphonate into the right testis to study the possible role of these macrophages during the prepubertal development of Leydig cells. The contralateral testes were injected with 0.9% NaCl and served as controls. The animals were injected with the liposomes and NaCl at 5, 10, 15, 20 or 25 days of age. In macrophage-depleted testes, Leydig cell development was inhibited in the animals injected at 5, 10 or 15 days of age. At 35 days of age, the testis was repopulated with macrophages and Leydig cells also developed. Rats treated at 20 or 25 days of age, when Leydig cells were already present in low numbers, did not show any further increases in the number of Leydig cells up to 35 days of age. To study whether the effects of gonadotrophins on Leydig cell development require the presence of macrophages, 21-day-old rats, injected 3 days before with liposomes (right testis) and NaCl (left testis), were treated with 75 iu human FSH kg-1 bodymass day-1, 10 iu hCG per rat day-1, combined hFSH and hCG, or vehicle (PBS with 0.5% BSA) for 6 days. Treatment with hCG induced a sevenfold increase in the number of Leydig cells in the left (macrophage-containing) testis, whereas no increase was found in the right (macrophage-depleted) testis. These results indicate that macrophages are needed for Leydig cell development and for the Leydig cell response to hCG during postnatal maturation.

Animals↗
PubMed1987

The ultrastructure of normal fetal and neonatal pig testis germ cells and the influence of fetal decapitation on the germ cell development.

The development of germ cells in the male pig was investigated ultrastructurally in normal and decapitated fetuses. The age ranged respectively from 30 days p.c. till one month after birth and from 52 days p.c. until birth. The ultrastructural organization of the germ cells changes dramatically between 30 days p.c. and 52 days p.c. which coincides with the formation of 'true' sex cords. From 52 days p.c. onwards the morphology is rather stable: cells show a 'hydrated' appearance and typical cell bridges. There is no obvious difference in the ultrastructure of germ cells in decapitated animals, their normal littermates and control animals. Therefore germ cell development in the pig is likely to be insensitive to gonadotropins during the fetal period. The development of pig germ cells follows closely the pattern described for several species. Quantitatively there is an increase in the ratio of germ cell/Sertoli cell per cross sectional diameter in the decapitated animals.

Animals↗
PubMed1988

Encephalopathy following cisplatin, bleomycin and vinblastine therapy for non-seminomatous germ cell tumour of testis.

A 22-year-old man developed severe encephalopathy, grand mal seizures and visual disturbance after combination chemotherapy with cisplatin, vinblastine and bleomycin for metastatic testicular carcinoma. After excluding treatable causes, only supportive management was given, and the symptoms and signs resolved over several months. We suggest a clinical syndrome of encephalopathy, seizures and visual disturbance represents a rare toxicity of cisplatin-based therapy. Given the wide spread usage of cisplatin, this should be drawn once again to the attention of medical oncologists.

Adult↗
PubMed1990

Zinc deficiency and dipeptidyl carboxypeptidase activity. Comparative effects on epididymis and testis of rats.

Dipeptidyl carboxypeptidase (DC) is highly active in the testis and epididymis of rats and increases during pubertal development. Zinc deficiency during this period depresses the activity of DC in the testis. Experiments were conducted to determine the effects of zinc deficiency on epididymal DC activity. Comparisons were made between changes seen in this organ and those observed in testis. Three dietary treatments were used; zinc-deficient, fed ad libitum; zinc-adequate, pair-fed to the deficient group; and zinc-adequate, fed ad libitum. Results confirmed that testicular DC is affected negatively by zinc deficiency. DC activity was also lower in the epididymis of zinc-deficient rats than in control rats. These effects apparently were specific relative to changes in activity of other enzymes. Alkaline phosphatase activity in the epididymis was not affected by zinc deficiency and it was depressed in the testis. Gamma-glutamyl transferase activity in the epididymis was not affected by zinc deficiency but it was elevated in the testis. The results of this study suggest that part of the effect of zinc deficiency on sexual maturity in the male rat may be caused by reduced activity of DC. This enzyme is thought to be required for maturation and development of sperm cells.

Alkaline Phosphatase↗