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PubMed1983

Transport of free and conjugated steroids from the boar testis in lymph, venous blood and rete testis fluid.

In 12 anaesthetized boars the concentrations of oestrone sulphate and dehydroepiandrosterone sulphate (DHAS) were 15- to 35-fold higher in lymph collected from a vessel in the spermatic cord than in testicular venous blood plasma from a vein in the spermatic cord. The concentrations of testosterone, total unconjugated oestrogens and dehydroepiandrosterone (DHA) were about twofold higher in lymph. The concentrations of all steroids studied were higher in testicular venous blood plasma than in arterial blood plasma (testosterone about sixfold; total unconjugated oestrogens about fourfold; oestrone sulphate about threefold; DHA and DHAS about twofold), but the concentrations of testosterone, total unconjugated oestrogens and oestrone sulphate in rete testis fluid were comparable to those in arterial blood plasma. Lymph flow from the pig testis was about 7% of plasma flow so that about 80% of the oestrone sulphate and DHAS produced by the testis leaves the organ in the lymph; the comparable values for testosterone, total unconjugated oestrogen and DHA were about 20%. In the 90-min period following an injection of human chorionic gonadotrophin there were substantial increases in the concentration of testosterone and smaller increases in the other steroids in arterial and spermatic venous blood plasma and in testicular lymph, but not in rete testis fluid; there were also small increases in lymph flow, but no change in blood flow.

Androgens↗

PubMed1990

[Cell junctions between Sertoli cells and the blood-testis barrier in goldfish testis].

Freeze-fracture and etching technique combined with thin sectioning and lanthanum impregnation has been used for the study of Sertoli cell junctions and the blood-testis barrier formation in goldfish testis with lobular organization. Some observations and results are first given in this paper. The results of experiments can be summarized as the following: 1). Sertoli cell junctions are compound junctions of tight junctions, desmosomes and gap junctions. Tight junctions usually appear as parallel or network like ridges on the P face and fine grooves on the E face at the freeze-etching replicas. Desmosomes and gap junctions often are located between or nearby the ridges of tight junctions. In addition, endoplasmic reticulum cristae near the junction area can also be observed. 2). The number, area and density of each individual junction vary with the development and differentiation stages of germinal cells in the cyst. 3). Tight junctions can be observed at any stage during germinal cell differentiation through the period of spermatogenesis and spermiogenesis. However, they appear morphologically different as type I and type II. 4). Lanthanum can partially penetrate into the intercellular spaces of spermatogonium and early primary spermatocyte but can't penetrate after the stage of late primary spermatocyte. 5). The blood-testis barrier formation starts at the stage of pachytene spermatocytes. The formation of the blood-testis barrier is the result of the development of the tight junction from type I to type II.

Animals↗

PubMed1992

Temporal correlation between the appearance of testis-specific DNA-binding proteins and the onset of transcription of the testis-specific histone H1t gene.

The histone H1t gene is transcribed only in testis. Northern blot analyses reveal that transcription of the H1t gene occurs first in pachytene primary spermatocytes. Thus, there is a temporal correlation between onset of transcription of the gene and synthesis of histone H1t in primary spermatocytes during spermatogenesis. Previous studies revealed that replacement of most H1t and core histones occurs during the midspermatid stage of spermiogenesis by transition proteins TP1 and TP2. In this paper we extend our study of the specific binding of testis nuclear proteins to a unique sequence element within the H1t promoter. The relatively tight binding is competed with an excess of homologous DNA but not with a mutated element. Testis proteins from prepubertal animals do not bind to the 18-bp promoter element out proteins from enriched populations of primary spermatocytes do bind. Therefore, the temporal correlation between onset of transcription of the H1t gene and the time when the specific H1t promoter-binding proteins are detected in primary spermatocytes suggests that the DNA-binding proteins might be germinal cell-specific transcription factors that participate in formation of an active H1t transcription initiation complex. These studies present the first analysis of binding sites for testis nuclear proteins from primary spermatocytes within the promoter of a gene expressed only during this stage of spermatogenesis.

Animals↗

PubMed1987

Nucleotide sequence of testis-derived c-abl cDNAs: implications for testis-specific transcription and abl oncogene activation.

The c-abl gene codes for a protein-tyrosine kinase and is expressed in most examined murine cell types as two distinct mRNA species of 5.5 kilobases (kb) and 6.5 kb. In mouse testis, an additional species of 4.0 kb is expressed in very high levels. To study the interrelationship between various c-abl transcripts and to compare their sequence with the v-abl transcript, we prepared c-abl-specific cDNA clones from mouse testis and determined the complete nucleotide sequence of the 4.0-kb cDNA that appears to be the reverse transcript of the testis-specific mRNA. In addition, we have determined the 3' sequence of an additional clone derived from the larger mRNA species that is expressed in somatic as well as germ-line cells. These cDNA sequences have been compared with the v-abl sequences to understand the mechanism of activation of this oncogene. The results demonstrate that (i) testis-specific c-abl mRNAs arise as a result of 3' truncation, and (ii) the v-abl gene has arisen from its cellular homologue as a result of an extensive deletional/mutational process.

Amino Acid Sequence↗

PubMed1969

A blood-testis barrier restricting passage from blood into rete testis fluid but not into lymph.

1. A permeability barrier in or around the seminiferous tubules of rams has been demonstrated by studying the rate of passage of a variety of substances from blood plasma into fluid collected from the rete testis and into testicular lymph.2. All substances studied passed readily into testicular lymph.3. Tritiated water, urea, ethanol and bicarbonate in rete testis fluid equilibrated with blood plasma within 3 hr; Na(+), K(+), Rb(+), Cl(-), I(-), CNS(-), creatinine and galactose entered slowly and p-aminohippurate (PAH), glutamate, iodinated albumin, inulin and [(51)Cr]EDTA did not appear in rete testis fluid at all.4. Rubidium was excluded relative to iodoantipyrine from the testes of control and hypophysectomized rats and from rat testes heated to 37, 40, 43 and 45 degrees C; no such exclusion was seen in testes of rats which had been given cadmium chloride 5 months earlier so as to destroy the seminiferous tubules.5. It is suggested that this permeability barrier will regulate the access to the seminiferous epithelium of some constituents of blood plasma, isolate the germinal cells immunologically and help to maintain the concentration differences between rete testis fluid and lymph or blood plasma.

Albumins↗

PubMed1988

In vitro model of the first phase of testicular descent: identification of a low molecular weight factor from fetal testis involved in proliferation of gubernaculum testis cells and distinct from specified polypeptide growth factors and fetal gonadal hormones.

The gubernaculum testis is the connective tissue organ that causes the testis to descend. How the process of testicular descent is regulated is not fully understood. Current hypotheses postulate that a nonandrogenic fetal testicular factor controls the first phase of descent, that is characterized by growth of the gubernaculum and transabdominal migration of the testis. When gonadal extracts from fetuses with ages corresponding to the first phase of testicular descent (50, 60, and 75 days) were tested on gubernacular cells, the growth stimulatory effect of testicular extracts exceeded the effect of both ovarian extract and fetal calf serum. Gonadal extracts from 80-, 90-, and 100-day-old fetuses showed only a minor sex difference. No sex difference or age-dependent changes were detected when fetal gonadal extracts were tested on murine 3T3 cells. Polypeptide growth factors (epidermal growth factor, insulin, fibroblast growth factor, platelet-derived growth factor, and transforming growth factor-beta) were tested for growth stimulatory activity and had only minor effects on gubernaculum cells. Fetal testicular hormones (anti-Müllerian hormone, inhibin, and androgenic steroids) did not induce initiation of DNA synthesis at concentrations that are highly bioactive in typical target systems. When testicular samples were dialyzed, the high mol wt fraction (greater than 3500) had lower growth stimulatory activity in gubernaculum cells, but not 3T3 cells. Bioactivity of ovarian extracts and fetal calf serum was not diminished after dialysis. The low mol wt fraction (less than 3500) of testicular extract was distinctly stimulatory to gubernaculum cells but not 3T3 cells, and the low mol wt fraction of ovarian extracts did not stimulate growth in either cell type. It was concluded that the fetal porcine testis during the first phase of testicular descent contains low mol wt factor(s) to which gubernaculum cells and not 3T3 cells are responsive. The bioactive fraction probably contains the factor(s) that initiate testicular descent. We suggest the name descendin for this new activity.

Androgens↗

PubMed1984

[Microsomal glucose 6-phosphate dehydrogenase in the rat testis--an testis--specific isoenzyme?].

Mammalian tissues contain cytosolic and microsomal glucose 6-phosphate dehydrogenase (G6PD). In the present study it was examined whether the microsomal G6PD in liver and testis of the rat are homologous. Kinetic parameters and immunological reactivity were estimated using rabbit antiserum against mice erythrocyte G6PD. Kinetic parameters allow to distinguish cytosolic and microsomal G6PD in rat liver but not in testis, whereas the immunological properties of the testis enzymes are different. The cytosolic G6PDs from liver and testis of the rat are identical enzymes having extremely similar properties to mice erythrocyte G6PD. The microsomal G6PD of both organs are not homologous enzymes. Testicular microsomal G6PD is likely to be an organ specific G6PD-isoenzyme.

Animals↗

PubMed1991

A national programme for testis cancer, the Irish Testis Tumor Registry (ITTR).

The fundamental aims of the ITTR are to perform research into testis cancer and maximize nationwide disease control. Authors compare regional trends: Ireland, England and Wales. In Ireland, between 1961 and 1984 in the 25 to 34 years age group, the mortality rate increased 123%. In contrast, in England and Wales, the number of deaths has decreased by 17%. The highest mortality rates of all, occurred in those Irish aged over 75 years old. The Irish incidence of testis cancer is 2.4 per 100,000 males per year. Seven countries have lower levels than Ireland, while ten countries have higher levels. Incidence was highest in young adults (5.8 per 100,000) with a moderate level seen in the elderly (1.8 per 100,000). Cases of testis cancer, in Ireland, were grouped as seminomas (45%, n = 101) or non seminomas (55%, n = 131). In seminomas, overall three year actuarial survival was 80%, stage I = 94%, stage II = 72% and stages III and IV = 23%. A variety of treatments were utilized and the results are presented. In non-seminomas, overall three year actuarial survival was 65%, with stage I = 95%, stage II = 54% and stages III and IV = 24%; a variety of treatments were used. A further study was designed ot establish whether personnel and the manner of management can influence the outcome in testis cancer. Survival in patients not receiving full dose cytotoxics was significantly lower than those receiving standard doses. Survival was reduced from 72% to 64% when marker assays were omitted and infrequent monitoring with CT scan was associated with reduced survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Health Knowledge, Attitudes, Practice↗

PubMedDate not supplied

[Scanning electron and light microscopic studies of the surface epithelium of the rete testis and epididymis of the boar. I. Rete testis and efferent ducts].

The use of the scanning electron microscope gave a three dimensional representation of the epithelial surface. Additionally, light microscopy revealed the representative structure of the epithelium. The rete testis showed a single layer of cubic epithelial cells. Short and dense microvilli were found on the surface. Sporadically a single, cilia-like structure was recognized. An extratesticular rete testis was identified. The flowing transition of the epithelium between the rete testis and the efferent ductuli occurred at different levels, so that both kinds of epithelial structures were recognized in the same area. The efferent ductuli were composed of a single columnar epithelium consisting of two cell types, principal cells and ciliated cells. The ciliated cells were recognized by their cilia protruding into the lumen. The principal cells showed microvilli on their surface and bleblike apical protrusions which erupt into the lumen.

Animals↗

PubMed1990

Adenomatous hyperplasia of the rete testis in the undescended testis.

Multiple foci of micronodular or tubulopapillary structures were noted in the rete testis of 13 cases of undescended testes. These structures were lined by low columnar to cuboidal epithelium, showed back-to-back crowding, and were supported by a thin lamina propria. These changes, referred to as adenomatous hyperplasia of the rete testis, appear to be a frequent finding in the undescended testis. An age-matched control group did not show any of these features.

Adolescent↗

PubMed1979

The role of the epididymis in descensus testis and the topographical relationship between the testis and epididymis from the sixth month of pregnancy until immediately after birth.

The position of the testis, the relationship between the epididymis and the testis, as well as the development and regression of the gubernaculum were investigated in 18 testicles of children from the 26th week of pregnancy until a few weeks after birth. The most important role in descensus testiculorum is ascribed to the differentiation of the epididymis and the ductus deferens. It is androgen dependent. The testis descends in the processus vaginalis, being attached to its dorsal wall.

Epididymis↗

PubMed1993

Circular transcripts of the testis-determining gene Sry in adult mouse testis.

Sry is expressed at higher levels in the adult testis, where no function has been determined, than in the genital ridge, its critical site of action. cDNA and 5' RACE clones isolated from testis or from Sry-transfected cell lines have an unusual structure, with 3' sequences located in a 5' position. RNAase protection assays and reverse transcription polymerase chain reactions confirmed that these unusual RNA molecules represent the most abundant transcript in testis. Furthermore, oligonucleotide hybridization and RNAase H digestion proved that these Sry RNA molecules are circular. Similar transcripts were detected in the testes of mice with Mus musculus musculus, Mus musculus domesticus, and Mus spretus Sry genes. The circular RNA is found in the cytoplasm but is not substantially bound to polysomes. We suggest that the circles arise from normal splicing processes as a consequence of the unusual genomic structure surrounding the Sry locus in the mouse.

Animals↗

PubMed1978

Study of follitropin receptors in testis using a homologous system. Binding of porcine follitropin to plasma membranes from immature porcine testis and correlation with adenylate cyclase stimulation.

The properties of follitropin receptors in immature porcine testis were determined using highly purified porcine follitropin. 1. The characteristics of follitropin binding to a subcellular fraction rich in plasma membranes were studied using a 125I-labelled follitropin with high specific activity (75-100 Ci/g) and high binding activity. The binding is dependent on time, temperature and pH. It is specific to follitropin as demonstrated by the very low binding activity of the follitropin alpha and beta subunits and of the other glycoprotein hormones. Scatchard analysis of binding data indicated an equilibrium association constant of 2 x 10(10) M-1 and a concentration of high affinity binding sites of 500 fmol/mg membrane proteins. 2. A sensitive radio-ligand receptor assay was developed. Fifty percent inhibition of binding was obtained with as little as 2 ng of porcine follitropin. Ovine and bovine follitropins and pregnant mare serum gonadotropin gave binding inhibition curves parallel to that given by porcine follitropin. With equine and human follitropin, significantly different slopes were recorded. 3. Kinetics of dissociation of labelled follitropin from its testis receptors showed the presence of at least two compartments with fast and slow dissociation rate constants. The ratio between the sizes of the slow and fast compartments appeared dependent upon preincubation time. 4. A temporal correlation was observed between binding of follitropin to testis receptors and activation of membrane bound adenylate cyclase.

Adenylyl Cyclases↗

PubMed1992

A new technique examines the connective tissue framework in normal testis and in testis cancer.

A method of cellular digestion known as Etching facilitated scanning electron microscopy (SEM) of the connective tissue framework in normal testis and in cases of testis cancer. The collagen in the seminiferous tubules in normal testis has distinct lamellae and a well-defined outer border. In the germ cell tumours examined, the tubular connective tissue appeared hypertrophied, the distinct outer border was maintained in a seminoma specimen unlike in a case of non-seminoma. In a specimen of non-germ cell lymphoma there was gross distortion of the tubular connective tissue. These apparent variations in the collagen framework may have implications regarding local tumour development.

Collagen↗

PubMed1995

Anti-müllerian hormone and anti-müllerian hormone type II receptor messenger ribonucleic acid expression during postnatal testis development and in the adult testis of the rat.

Anti-müllerian hormone (AMH) induces degeneration of the müllerian ducts during male sex differentiation and may have additional functions concerning gonadal development. In the immature rat testis, there is a marked developmental increase in AMH type II receptor (AMHRII) messenger RNA (mRNA) expression in Sertoli cells, concomitant with the initiation of spermatogenesis. AMHRII mRNA is also expressed at a high level in Sertoli cells in adult rats. To obtain information about the possible functions of AMH in the testis, we investigated the postnatal expression patterns of the genes encoding AMH and AMHRII in the rat testis in more detail. Using RNase protection assays, AMH and AMHRII mRNA expression was measured in total RNA preparations from testes or testicular tubule segments isolated from control rats and from rats that had received various treatments. The testicular level of AMHRII mRNA was found to be much higher than that of AMH mRNA in adult rats. AMH mRNA was detected at a maximal level at stage VII of the spermatogenic cycle and at a low level at the other stages. AMHRII mRNA increases from stage XIII, is highest at stages VI and VII, and then rapidly declines at stage VIII to almost undetectable levels at stages IX-XII. It was found that the increase in testicular AMHRII mRNA expression during the first 3 weeks of postnatal development also occurs in sterile rats (prenatally irradiated), and hence, is independent of the presence or absence of germ cells. Yet, the total testicular level of AMHRII mRNA was decreased in sterile adult rats (prenatally irradiated or experimental cryptorchidism), as compared with intact control rats. However, treatment of adult rats with methoxyacetic acid or hydroxyurea, which resulted in partial germ cell depletion, had no effect on total testicular AMHRII mRNA expression. We conclude that a combination of multiple spermatogenic cycle events, possibly involving changes of Sertoli cell structure and/or Sertoli cell-basal membrane interactions, regulate autocrine AMH action on Sertoli cells, in particular at stage VII of the spermatogenic cycle.

Age Factors↗

PubMed1975

Steroid entry into rete testis fluid and the blood-testis barrier.

Evidence that steroids enter rete testis fluid (RTF) from the blood at varying rates was obtained during i.v. infusions into rats. Testosterone and dehydroepiandrosterone were readily transferred into the fluid, whereas cholesterol was excluded. Between these extremes, the appearance of radioactivity in the RTF suggested the following order of entry rate: progesterone greater than pregnenolone greater than 5-alpha-reduced androgens greater than oestrogens greater than corticosteroids. Preliminary identification of metabolites in RTF and blood suggested that testosterone and dehydroepiandrosterone were transferred largely unchanged. Androstenedione and progesterone, however, were largely metabolized during transfer into the RTF, the former being transformed to testosterone. The results are used to discuss the nature of the blood-testis barrier to steroids and the source of androgens in the RTF.

Androgens↗

PubMed1994

Neonatal testis tumors: a review of the Prepubertal Testis Tumor Registry.

Since 1980, 338 testis tumors have been registered in the Prepubertal Testis Tumor Registry of the American Academy of Pediatrics, Section on Urology. Of these tumors 22 occurred in neonates less than 1 month old, of which 7 (31%) were diagnosed at birth. The distribution of lesions in this group revealed 6 yolk sac tumors, 6 gonadal stromal tumors, 6 juvenile granulosa cell tumors, 2 gonadoblastomas, 1 teratoma and 1 hamartoma. Preoperative serum alpha-fetoprotein levels were available for 10 patients and ranged from 23 to 61,700 ng/ml., which is within normal limits. No patient had evidence of metastatic disease at presentation. Of the 18 children in whom follow up is available 17 have no evidence of disease and 1, who was diagnosed with a yolk sac tumor before the advent of chemotherapy, died of metastatic disease before reaching age 1 year. Although neonatal testis tumors are rare, they should be considered in the differential diagnosis and management of a newborn with a scrotal mass.

Follow-Up Studies↗

PubMed1992

[Epidermoid cyst of the testis: a case of testis preservation].

A 19-year-old man complained of an asymptomatic right testicular mass. Physical examination revealed a firm, small-finger sized, mass lesion with a smooth surface in the right testis. The ultrasonographic appearance was hypoechoic and well-demarcated intratesticular lesion. All laboratory investigations, including tumor markers, were normal. The testis was explored through an inguinal incision. The mass was excised locally and the biopsy of the adjacent testicular tissue was done with gentle code clamping. The histological diagnosis was epidermoid cyst of the testis and the testicular tissue obtained was normal. About 90 cases of testicular epidermoid cyst have been reported in the Japanese literature, and are reviewed briefly here.

Adult↗