Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “testis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,189 records · Page 66Linked to original sources
PubMed1997

Chromosomal assignment of 311 sequences transcribed in human adult testis.

A total of 311 expressed sequence tags (ESTs) derived from human adult testis have been assigned to human chromosomes by Southern analysis of a monochromosome somatic cell hybrid panel. Over 70% of the ESTs show conservation to hamster and mouse DNA, and the overall distribution of transcripts correlates well with physical chromosome size and to a greater extent with male meiotic chromosome length. The notable exception is the X chromosome, for which the number of testis-derived ESTs is greatly underrepresented. This finding may reflect inactivation of the X chromosome during the meiotic phase of spermatogenesis and a consequent selection against large numbers of X-linked germ cell transcripts. Further analysis of the distribution of testis ESTs showed that the EST density remains significantly correlated with the recombination density of each autosome. Analysis of a comparable number (320) of brain EST autosome assignments showed no similar correlation. These data suggest a specific association between transcription in testis tissue and male meiotic recombination.

Adult↗
PubMed1997

Genomic characterization of a testis-specific TFIIS (TCEA2) gene.

There is a family of genes encoding TFIIS-related proteins in human cells. We have focused upon the genomic organization of one family member expressed primarily in the testis. This gene encodes a transcription elongation factor similar to but distinct from that encoded by a previously reported TFIIS gene. Also in contrast to the previously reported TFIIS gene, the testis gene contains introns. All exon-intron junction sequences match the consensus GT/AG rule. The gene consists of seven exons and six introns with a total size of approximately 7 kb. The nucleotide sequence of the 5 flanking region of the testis TFIIS gene contains several potential regulatory factor-binding sites, not all of which are present in the TFIIS gene, whose expression is nearly ubiquitous. Elucidation of the full structure of the testis TFIIS gene should be useful for determining its chromosomal localization and its potential role in the regulation of gene expression in human tissues.

Animals↗
PubMed2001

Spermatogenesis by Sisyphus: proliferating stem germ cells fail to repopulate the testis after 'irreversible' injury.

2,5-Hexanedione is the toxic metabolite resulting from oxidation of the commonly used solvents n-hexane and methyl n-butyl ketone. Exposure to 2,5-hexanedione or its precursors results in a slowly progressive peripheral polyneuropathy and testicular injury. The chemical basis of the injury involves reaction of 2,5-hexanedione with protein amines, such as the epsilon-amine of lysine, to form pyrroles which further react to form protein-protein crosslinks. The target cell of injury in the testis is the supportive cell in the seminiferous epithelium, the Sertoli cell. A major function of the Sertoli cell is to nurture the dependent germ cell population by secreting seminiferous tubule fluid. 2,5-Hexanedione-induced crosslinking of the microtubule subunit protein, tubulin, leads to altered Sertoli cell microtubule-dependent transport and deficient formation of seminiferous tubule fluid, compromising germ cell viability. In an established model of testicular injury, rats are exposed to 1% 2,5-hexanedione in the drinking water for a period of 3-5 weeks. Three weeks after initiating exposure, decreased seminiferous tubule fluid secretion initiates a wave of germ apoptosis which peaks during the 5th week. The germ cell content of the injured testis continues to decline after cessation of the exposure, reaching a nadir during the 12th week. From this time onward, the testis is severely atrophic with less than 1% of seminiferous tubules in a testicular cross section containing germ cells more advanced than spermatogonia. Interestingly, this persistent state of post-injury 'irreversible' atrophy in the rat is characterized by the presence of a proliferating stem germ cell population which produces differentiating spermatogonia which then die by apoptosis. Serial cross sections of bromodeoxyuridine-labeled testis were analyzed to determine the kinetics of stem germ cell proliferation. Approximately 40% of stem cells (identified as single cells in the seminiferous epithelium) were actively proliferating with a cell cycle time of 8-14 days. Analysis of the total germ cell population present and modeling using the known cell cycle times of differentiating spermatogonia indicated a block in differentiation at the level of type A3/A4 spermatogonia. Quantitation of the frequency of apoptosis indicated that all of the germ cells died prematurely by this mechanism. Leuprolide is a gonadotropin-releasing hormone agonist which produces a profound suppression of testosterone levels with chronic administration. When delivered as a series of 3 depot injections 24 days apart, leuprolide resulted in a partial reversal of the 2,5-hexanedione-induced persistent atrophy. The reinitiation of spermatogenesis follows a lowering of the intratesticular testosterone concentration, indicating that intratesticular testosterone is at least partially responsible for the persistent atrophy. The efficacy of leuprolide-induced reversal of the persistent atrophy decreases with time after injury, suggesting that atrophic seminiferous tubules are initially capable of recovery and then enter a state of irreversible injury. Injection of ethane dimethane sulfonate at the beginning of leuprolide treatment eliminated Leydig cells during therapy and ablated the recovery of spermatogenesis, indicating that a Leydig cell-associated paracrine factor is required to restart spermatogenesis. The rat, therefore, has multiple states of testicular germ cell proliferation: normal spermatogenesis and at least two forms of persistent atrophy (leuprolide reversible and leuprolide non-reversible). Partial reversal of the persistent atrophy can be achieved by lowering intratesticular testosterone. Ongoing experiments are designed to address the role of the Leydig cell in post-injury recovery, and to further characterize the molecular events contributing to the different states of persistent atrophy.

Animals↗
PubMed1986

Macrophages in the interstitial tissue of the rat testis.

Macrophages were identified in the intertubular tissue of the rat testis by loading animals with a particulate vital dye (trypan blue or India ink) and by localizing immunocytochemically a macrophage membrane antigen (MRC W3/25). Leydig cells were identified by the histochemical staining reaction for 3 beta-hydroxysteroid dehydrogenase activity and by a monoclonal antibody. Macrophages were scattered in the interstitial tissue closely attached to and mixed with the Leydig cells. They were never found in the seminiferous tubules. The macrophages comprised about 25% of all the cells in the interstitium. Double staining with a vital dye and a marker antibody showed that all the phagocytosing cells were macrophages and that the Leydig cells did not take up vital dyes. Double staining for the demonstration of the 3 beta-hydroxysteroid dehydrogenase activity and the macrophage antigen likewise revealed two distinctly different cell populations. Crude Leydig cell preparations obtained by collagenase treatment of the testis contained macrophages (12-14%). Macrophages were present throughout the postnatal prepuberal development of the testis. Their density was increased in the cryptorchid and irradiated testis.

3-Hydroxysteroid Dehydrogenases↗
PubMed1988

Lactate dehydrogenase isoenzymes in prostate and testis of wild animals and some histological remarks.

The lactate dehydrogenase (LDH) isoenzyme pattern of prostate and of testis of 27 wild animals showed that in several species more than 5 isoenzymes are detected, with electrophoretic mobilities different to those found in humans. The LDH-X band, found in testis from mature humans is also observed in the testis of wild animals. However, in several species more than one LDH-X is found. The results obtained demonstrate their usefulness in phylogeny. The prostate gland and testis of the chimpanzee show the greatest resemblance to man. Histological examination of the prostate glands seems to correlate with the phylogenetical classification of the mammals studied.

Animals↗
PubMed1990

Differentiation-related changes in the distribution of glycoconjugates in rat testis.

The distribution of glycoconjugates in differentiating rat testis was investigated by fluorescein labeled lectins during embryogenesis and postnatal development. Double immunofluorescence with rhodamine coupled laminin antibodies was used to delineate testicular cords from the interstitium in embryonic testes. Rat testis was found to be rich in various glycoconjugates, with distinct differentiation-related changes in their distribution. All types of germ cells contained carbohydrate rich compounds in their cytoplasm. Glycosylation in the embryonic testis was different from that in the adult rat. At an early stage of testicular differentiation, the labeling of germ cells and other testicular cells was almost identical. The lectin binding patterns of embryonic germ cells and somatic cells were related to the developmental age of the animal, with a graded disappearance of galactose containing glycoconjugates in embryonal spermatogonia. Spermatogenic cell differentiation was characterized by striking changes in lectin binding patterns of germ cells, particularly in the acrosomes of developing spermatids, in relation to their functional activation and the emergence of adult type of glycosylation during the postnatal maturation of the testis. As the knowledge of regular glycosylation throughout tissue differentiation is of significance for the analysis of aberrant glycosylations occurring in pathologic disorders, our findings suggest the usefulness of lectin histochemistry for the studies on germ cell differentiation.

Animals↗
PubMed1995

Immunohistochemical localization of the calcium/calmodulin-dependent protein phosphatase, calcineurin, in the mouse testis: its unique accumulation in spermatid nuclei.

Immunohistochemical localization of a calmodulin-dependent protein phosphatase, calcineurin, was studied in the mouse testis in relation to previous observations showing that calmodulin is unusually rich in spermatogenic stages from mid-pachytene spermatocytes to elongating spermatids. The antibodies raised against calcineurin from scallop testis reacted with subunit B, but not subunit A, of calcineurin isoforms from mouse brain and testis. Indirect immunofluorescence using these antibodies on the mouse testis revealed positive reactions only in the nuclei of round or elongating spermatids: calcineurin started to accumulate in nuclei from the acrosomal cap phase, peaked at the initial stage of nuclear elongation, and decreased thereafter. There was almost no signal in the cytoplasm; spermatogenic cells at other stages, including spermatogonia, spermatocytes, mature sperm, and other somatic cells in the seminiferous tubules were totally negative. Immuno-electron microscopy gave the same result, on the basis of measuring the density of immunogold particles. These results suggest a role for calcineurin in remodeling of the nuclear chromatin in metamorphosing spermatids.

Animals↗
PubMed1995

NPY- and CGRP-like immunoreactive nerve fibers in the testis and mesorchium of the toad (Bufo arenarum).

The presence and distribution of peptidergic nerve fibers were studied in the testis and mesorchium of the toad by means of immunohistochemistry. Cryostat sections of the testis and whole-mount preparations of mesorchia were immunostained with antisera to calcitonin gene-related peptide (CGRP) and neuropeptide tyrosine (NPY). After leaving the mesorchium CGRP-immunoreactive (IR) fibers were seen predominantly running in between the seminiferous tubules. In addition, a small population of CGRP-IR nerve fibers formed thin plexuses around blood vessels. Conversely, NPY-like immunoreactivity predominated in nerve fibers that formed dense plexuses around vessels both in the mesorchium and testis. Additionally, some single NPY-IR nerve fibers could be seen in both structures studied. The functional significance of these peptidergic systems in the testis of the toad remains to be analyzed.

Animals↗
PubMed1991

Immunohistochemical distribution of sulfhydryl oxidase in the human testis.

Sulfhydryl oxidase (SOx) is an enzyme that catalyzes the oxidation of sulfhydryl compounds. It is present in mitochondria of certain testicular cells at specific stages of functional activation. In the mature human testis moderate SOx immunoreactivity is found in Leydig cells, and lacking in Sertoli and in peritubular cells. The Adark spermatogonia usually contain immunoreactive mitochondria, while in Apale spermatogonia immunoreactivity is mostly low. In stage V of spermatogenesis, Apale spermatogonia were found containing immunoreactive material. Leptotene (stages IV and V) and zygotene (stage VI) primary spermatocytes display a moderate immunoreaction. It is strongest in pachytene spermatocytes of stages I-IV, decreases in stage V, and is low during diakinesis and in secondary spermatocytes. Late spermatids usually show a stronger immunoreactivity than early spermatids. At stage V of spermatogenesis the late spermatids contain only few immunoreactive particles. Spermatozoa are free of SOx-immunoreactive mitochondria. In residual bodies small amounts of SOx-immunoreactive particles are seen. Compared to rat and hamster testis, SOx immunoreactivity of the human testis is less clearly stage-dependent and it is not confined to certain germ cell stages. As deduced from the findings in patients with spermatogenic disorders, the SOx immunoreactivity of spermatogonia in human testis seems to be of diagnostic relevance.

Adult↗
PubMed1987

Effects of estrogens on the testis of transsexuals: a pathological and immunocytochemical study.

Testes from five male-to-female transsexuals removed during sex-reversal surgery after administration of estrogens were studied histologically and with immunoperoxidase procedures to locate estrogen receptors (ER) and related antigens. Atrophy of the seminiferous tubules was observed in all cases; its degree, and a marked decrease in Leydig cells, correlated with low plasma gonadotropin levels (rather than with the duration of treatment). In all cases, the rete testis appeared hyperplastic and the other components (efferent ductules, epididymus) well preserved. The efferent ductules proved to be the only structure where ER can be located by the ER-ICA procedure, whereas staining for the p 29 ER-associated antigen is strongly positive both here and in the rete testis. The immunocytochemical data, in parallel with the observed biological effects, indicate that the rete testis and the efferent ductules and, to a minor degree, the epididymus and Leydig cells are the main direct targets of estrogens in the human testis.

Adult↗
PubMed1987

Spatial topography of the excurrent duct system in the bovine testis.

The rete testis of the bull is situated within an axial mediastinum and consists of approximately 30 longitudinally arranged, anastomosing rete channels. At the cranial testicular pole all rete channels empty into a common space, the area confluens retis, which is subdivided by small septa and narrow chordae retis. The area confluens always contains numerous spermatozoa and is connected with the bulbous initial portions of the efferent ductules by short, often tortuous rete tubules. Since the connection between rete and efferent ductules is situated within the tunica albuginea, the bovine excurrent duct system is not provided with an extratesticular rete as in many other mammals. Straight testicular tubules merge from all directions to connect with superficial rete channels, but the inlets are not evenly distributed. In the periphery each straight tubule begins with a cup-like structure followed by a narrow stalk region and a heavily folded portion opening either immediately into a rete channel or into a tube-like lateral rete extension. In close contiguity to the rete testis lie extremely coiled arterial portions connecting the centripetal and the centrifugal branches of the testicular artery. Since intrinsic musculature is scarcely developed in the mediastinum, and transport of rete content relies primarily on massage due to external pressure changes, the pulsatile blood flow through these coiled arteries may influence conveyance processes within the rete testis. An intimate spatial association between area confluens retis and adjacent large, thin-walled lymph vessels may facilitate a transfer of androgens into the fluid of the rete testis.

Animals↗
PubMed1976

[Surgical technique in the management of undescenced testis (author's transl)].

In cases of retentio abdominalis or inguinalis and of ectopic testis, surgery is performed about the 2nd year of life. Essentials of the operating technique are: incision of the skin must not be parallel to the spermatic cord; testes and spermatic cord must be mobilized without trauma; ideally a biopsy of the testis should be taken; any pulling of the spermatic cord and torsion of it during fixation of the testis should be avoided. If initial tensionfree placement of the testis in the scrotum is impossible, the operation should be carried out in 2 sessions with an interval of 6-12 months. In 241 cases of children operated on from 1972-1975 with 308 total operations, the author observed 2 recurrences and 1 deep infection (scrotal abscess).

Adolescent↗
PubMed1997

Torsion of only spermatic cord in the absence of testis and/or epididymis results in contralateral testicular hypoxia.

Unilateral spermatic cord torsion in the presence or absence of ipsilateral testis causes hypoxia in the contralateral testis. An experimental study was conducted to find the most important structure that causes contralateral testicular hypoxia following ipsilateral twisting. In five groups each consisting of 10 rats sham operations, epididymoorchiectomy, spermatic cord torsion, spermatic cord torsion following subepididymal orchiectomy or spermatic cord torsion following epididymoorchiectomy were performed. Lactic acid, hypoxanthine and thiobarbituric acid reactive products of lipid peroxidation (TBAR) were determined in the contralateral testis. While lactic acid, hypoxanthine and TBAR values did not differ significantly following sham and epididymoorchiectomy procedures, evaluation of other groups revealed significantly increased values compared with sham and epididymoorchiectomy groups. Since torsion of only spermatic cord and testicular vasculature causes contralateral testicular hypoxia, testis and epididymis do not seem to be mandatory for occurrence of contralateral testicular hypoxia. Testicular artery under distress seems to be the most important structure that results in contralateral testicular hypoxia following torsion.

Animals↗
PubMed1986

Relationships between serum FSH level and the size of testis in azoospermic patients.

Sixty-eight out of 700 patients proved to be azoospermic at our Andrology Clinic between 1981 and 1983. According to the serum FSH level and testis size, three main diagnostic groups were established: 1. patients with occlusion but testis size and FSH level normal; 2. patients with smaller testis size and increased FSH level and primary spermatogenetic disorder; 3. non-palpable testis and increased serum FSH level referring also to testicular disorder. No correlations were found between serum LH and testosterone levels and testicular volume.

Follicle Stimulating Hormone↗
PubMed1978

Prostaglandin metabolism by human testis.

Human testis preparations appear to carry out both the synthesis and turnover of prostaglandins. Prostaglandins and prostaglandin metabolites were extracted from whole tissue. Testis microsomes converted both endogenous and exogenous substrate to prostaglandins. Microsomal prostaglandin biosynthesis was inhibited by indomethacin. Prostaglandin E2-9-ketoreductase was present in both the cytosolic and microsomal fractions of human testis. Prostaglandin metabolism by human testis has not previously been reported.

Aged↗
PubMed2004

Cloning of a novel gene, Cymg1, related to family 2 cystatins and expressed at specific stages of mouse testis development.

We have cloned a novel gene, Cymg1 (GenBank accession number AY600990), from a mouse testis cDNA library. Cymg1 is located in 2G3 of mouse chromosome 2. The cDNA includes an open reading frame that encodes 141 amino acid residues. The encoded polypeptide has a cysteine protease inhibitor domain found in the family 2 cystatins but lacks critical consensus sites important for cysteine protease inhibition. These characteristics are seen in the proteins of the CRES subfamily of the family 2 cystatins which are expressed specifically in the reproductive tract. CYMG1 protein shows 44% identity with mouse CRES and 30% identity with mouse cystatin C. Northern blot analysis showed that the Cymg1 gene was specifically expressed in adult mouse testis. RT-PCR also showed that Cymg1 was expressed in testis and spermatogonial cells. Cymg1 expression level varied in the different developmental stages of mouse testis, and were coincidental with spermatogenesis and sex maturation. These results indicate that Cymg1 may play important roles in mouse spermatogenesis and sex maturation.

Amino Acid Sequence↗
PubMed2003

Expression of mouse telomerase catalytic subunit mTERT gene in testis of SD rats and its significance.

To study the expression of mTERT gene in the testis of SD rats and its significance, in situ hybridization (ISH) techniques were used to detect the expression of telomerase gene mTERT mRNA in the testis of SD rats. The expression of mTERT was detectable in different-age male SD rats testis. There was a positive correlation between the expression of mTERT and the location of germ cells (spermatogonia, spermatocyte, spermatid). In Sertoli cells, leydig cell and spermatozoa, telomerase mTERT was not detected. Type A spermatogonia expressed the highest level of telomerase mTERT mRNA. Our results suggest that the expression of mTERT gene in the testis of SD rats is of lifetime and coincide with the telomerase activity.

Animals↗
PubMedDate not supplied

Alcohol-induced oxidative stress and reduction in oxidation by ascorbate/L-cys/ L-met in the testis, ovary, kidney, and lung of rat.

Chronic exposure to high doses of alcohol results in many pathophysiologic changes in cellular function caused by the alcohol itself and the effects of its metabolism (ie, generation of acetaldehyde, nicotinamide adenine dinucleotide [NADH], free radicals, and oxidative stress). However, the role of each of these effects on the testis, ovary, kidney, and lung in chronic alcoholism must be investigated. It is hypothesized that cysteine-methionine and vitamin C might neutralize harmful compounds and potentiate the antioxidant capacity of the cell or tissue. In this study, rats were fed regular diets and were maintained in the following groups for 90 days: control group; alcoholic group (2.5 g of 50% ethanol/kg body wt administered intragastrically every other day); and alcoholic with antioxidant supplement group (2.5 g of 50% ethanol plus a solution containing 200 mg vitamin C, 100 mg cysteine, and 100 mg methionine/kg body wt administered intragastrically every other day). After treatment had been completed, rat blood, testis, ovary, kidney, and lung were taken for biochemical analysis. Mean alcohol level in the alcoholic group was raised (by 40%) compared with that in the control group, but it was lower (by 30%) in the antioxidant-supplemented group than in the alcoholic group. In accordance with the levels of alcohol, oxidized protein and lipid content in the testis, ovary, kidney, and lung were low in the control group, higher in the antioxidant-supplemented group, and highest in the alcoholic group. It is interesting to note that levels of glutathione in the testis and lung of the alcoholic group were lower than those in both the control and antioxidant-supplemented groups. In conclusion, chronic alcohol administration led to a significant increase in the level of protein oxidation in the ovary and kidney of rats. Simultaneous intake of ascorbate/L-cys/L-met, along with ethanol, partly attenuated the amount of lipid and protein oxidation that occurred in tissues with oxidative stress caused by alcohol consumption.

Animals↗