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PubMed1990

Comparisons of endocrinological and testis parameters in 18-month-old Ile de France and Romanov rams.

Endocrinological and testis parameters of adult 18-month-old Ile de France (IF) and Romanov (Ro) rams were compared during sexual season. Testis weights, total volumes of intertubular tissue, and of blood and lymph vessels, total seminiferous tubule length, rete testis flow rate and daily production of germ cells were significantly higher in IF than in Ro rams. These variations originated from differences in Sertoli cell numbers, which were established before puberty. When daily productions of germ cells, of ABP or of RTF were expressed per Sertoli cell, they were higher in Ro than in IF rams. Quality of spermatids, as measured by their cellular size prior to elongation, was lower in Ro than in IF. The number of FSH-binding sites per Sertoli did not differ between the two breeds but FSH plasma levels were higher in Ro than in IF rams. Total numbers of Leydig cells per testis, their individual size or their LH-binding capacity did not differ significantly between the two breeds. However, the ratio of mean testosterone upon mean LH plasma levels were greater in Ro than in IF rams while both breeds had identical LH mean plasma levels.

Animals↗
PubMedDate not supplied

Cystic dysplasia of the testis: a report of three cases and review of the literature.

We describe the clinical and pathologic findings in three cases of cystic dysplasia of the testis and compare our findings to others in the English literature. The condition is characterized by dilatation of the rete testis with or without similarly affected adjacent structures. It is important to recognize this lesion for two reasons. First, it is associated with a high frequency of ipsilateral renal anomalies. Second, it is important to consider this condition in the differential diagnosis of cystic testicular mass in a neonate or a child. The management of this condition is quite different from the management of other testicular masses such as a hydrocele, testicular germ cell tumor, or infiltrative disorder (e.g., lymphoma, inflammation, torsion, or hematoma). Testicular cystic dysplasia is benign and the lesion can be removed surgically, leaving the rest of the testis intact. A discussion of the lesion's possible pathogenesis is also presented.

Antigens, Neoplasm↗
PubMed1980

[Effects of inhibin on the in vitro synthesis of desoxyribonucleic acid in the rat testis].

Three preparations of inhibin extracted from ram rete testis fluid (RTF) and from human seminal plasma (HSP) reduce tritiated thymidine incorporation into testicular desoxyribonucleic acids (DNA) in vitro. Effect of low molecular inhibin from RTF is dose-dependent. Castrated ram serum does not modify testicular DNA synthesis in vitro. Besides their suppressive action on follicle stimulating hormone (FSH) secretion in vivo and in vitro, these inhibin preparation display a direct inhibiting effect on testicular DNA synthesis and, thus, on mitotic activity. Identity between inhibin and testicular chalones are discussed.

Animals↗
PubMed1983

Evidence for protein absorption from the lumen of the seminiferous tubule and rete of the rat testis.

As luminal fluid moves from the seminiferous tubule and enters the rete testis, its protein concentration declines from approximately 6 mg/ml to 1 mg/ml. It was therefore suggested that protein is either 1) utilized by the spermatozoa, 2) transported across the epithelium of the terminal segment of the seminiferous tubule, the tubuli recti or rete testis, or 3) absorbed and degraded by the epithelium. Horseradish peroxidase (HRP), a protein marker, was microperfused into single seminiferous tubules or perfused directly into the rete. After fixation, the HRP was localized histochemically and the tissue observed under the light- and electron microscope. HRP was taken up via pinocytotic vesicles into the cytoplasm of the Sertoli cells and germ cells but did not permeate extracellularly beyond the tight junctions. Similar results were obtained in the cells lining the terminal segment and the tubuli recti. The rete epithelium showed uptake of HRP into coated and noncoated vesicles, while some cells additionally revealed diffuse cytoplasmic distribution of HRP. The terminal segment, tubuli recti, and rete testis may be important routes by which proteins may leave the testicular fluid either to be degraded or to enter the blood.

Absorption↗
PubMed1975

Permeability of selected drugs and chemicals across the blood-testis barrier of the rat.

Physiological studies by Setchell and others have described the existence of a blood-testis barrier (BTB) surrounding the seminiferous tubules of the mammalian testis. These studies were initiated to better define the role of the BTB with regard to the penetration of exogenous chemicals to male germ cells. The rete testis was cannulated in rats and fluid was collected. Test chemicals or drugs were usually administered by continuous i.v. infusion. Permeability of nonelectrolytes of various molecular sizes, acidic compounds with varying partition coefficients and pKalpha values, such as salicylic acid, barbiturates, and sulfonamides, across the BTB were studied. Permeability of nonelectrolytes was demonstrated to be dependent upon their molecular size, suggesting bulk flow through water-filled pores. On the other hand, permeability of acidic drugs with varying pKalpha values depended upon their partition coefficients. Transport of these chemicals from blood to seminferous tubules closely resembled their transport from blood to cerebrospinal fluid. It appears that the BTB is a complex multicellular system composed of membranes surrounding the semiferous tubules and the several layers of spermatogenic cells organized within the tubules, which restrict the permeability to the male germ cells of many foreign compounds. This must be borne in mind when extra-polating data from in vitro mutagenic test systems to man.

Animals↗
PubMed1988

Endocrine cells in the excurrent duct system of the testis. An immunohistochemical analysis.

A systematic search for endocrine cells in the excurrent duct system of the testis was carried out by means of histochemical and immunohistochemical techniques. A panel of antibodies against amine and polypeptide hormones was used. 80 specimens comprising representative areas of rete testis, ductuli efferentes, ductus epididymis and 30 examples of ductus deferens were investigated. Cells immunoreactive for serotonin were detected in four out of 110 specimens. They were invariably in normal-appearing ductuli efferentes. A salient feature was their rarity and focal distribution. We failed to detect any endocrine cells in other segments of the excurrent duct system and notably not among epididymal epithelium. It seems of interest that serotonin cells are specifically distributed throughout remnants of excretory mesonephric tubules in both males and females.

Endocrine Glands↗
PubMed1982

The testis and its excurrent ducts in American caenolestid and didelphid marsupials.

The present study examines and compares the structure of the testis and its excurrent ducts in a caenolestid and four didelphid marsupials. Of particular interest was the site of sperm pairing in the epididymis and whether this feature, shared by both American marsupial families but not by any Australian marsupial, was associated with changes in the morphology of the duct. In contrast to the testes of most Australian marsupials, except the peramelids (bandicoots), the intertubular space in the American marsupials was filled by Leydig cells (around 20% of testis volume). The opossum testes were unusual compared with those of eutherian mammals in that histological sections of individual seminiferous tubules contained only a single cellular association irrespective of the length of the tubule sectioned. The rete testis, as in the Australian dasyurids (devil, quoll, etc.), was a simple branching duct system that arose deep within the testis and emerged as a single duct at the testicular hilus. This arrangement is completely different from that in Kangaroos and Australian possums, indicating a diversity of rete form in the marsupials similar to that seen in eutherian mammals. The rete emptied into a single, essentially straight, efferent duct that became convoluted towards the epididymis, where it formed a distinct structure adjacent to the caput epididymidis. The efferent ducts were highly variable in diameter and epithelial height, suggesting that the duct was not of uniform character along its length, or that the initial single duct had divided to form ducts of different characters. Sperm pairs were first seen in the proximal cauda epididymis, and their appearance was correlated with changes in the character of the duct and its epithelium. The distal ductus deferens of Caenolestes, in contrast to those of the didelphids and indeed all other marsupials, was a convoluted ampulla-like structure adjacent to the prostate gland. In the other marsupials the only accessory sex glands are a segmented prostate and bulbourethral glands.

Americas↗
PubMed1978

Ageing changes in the human testis: a light-microscopic study.

A histologic study of ageing testes, removed surgically from 'healthy' men aged 52-100 years, is presented. The age-related changes noted were: tubular sclerosis, Leydig cell hyperplasia, focal mononuclear orchitis, capsular smooth muscle hyperplasia, and dilatation of the rete testis. Great individual variations were seen but the testes, removed from patients with prostatic carcinoma, showed less severe ageing changes than those removed from patients during herniorrhaphy. The aetiology and pathogenesis of these changes are briefly discussed. A plea is made for more systematic studies of the ageing human testis, combining light microscopy with more sophisticated techniques, such as electron microscopy, histochemistry and cytochemistry.

Aged↗
PubMedDate not supplied

Spermatophagy in the seminiferous tubules and excurrent ducts of the testis in Rhesus monkey and in man.

The fine structure of cells capable of phagocytosing spermatozoa in the testes and epididymes of monkeys and men was studied by means of transmission and scanning electron microscopy. Both resident cells, such as Sertoli cells and epithelia of the rete testis, and free cells, such as macrophages (spermatophages) were found to phagocytose spermatozoa or fragments of spermatozoa in the seminiferous tubules and excurrent ducts. The spermatophages develop from precursor cells which invade the seminiferous tubules. After phagocytosis of spermatozoa they increase in size and sometimes possess more than one nucleus. Large spherically shaped spermatophages are found in the epididymis. In the rete spaces of Macaca fascicularis spermatophages are able to penetrate the rete epithelia and reside in the subepithelial connective tissue layers. Spermatophagy is frequently seen in the gonads of older men and in certain cases of oligozoospermia. In Macaca an increased number of spermatophages occurs at the end of the spermatogenetic season.

Animals↗
PubMed2003

Characterization of fibroblast growth factor receptors expressed in principal cells in the initial segment of the rat epididymis.

Studies from our laboratory support a model in which growth factors produced in the testis reach the epididymis via the luminal system and play an important role in maintaining the function of epithelial cells, particularly in the initial segment. Previous work showed that gamma-glutamyl transpeptidase (GGT) mRNA IV, which is highly expressed in the rat initial segment, may be under the control of luminal fibroblast growth factor 2 (FGF-2) from the testis. The current studies were undertaken to identify which fibroblast growth factor receptors (FGFRs) are present in the principal cells of the rat initial segment and to identify other potential ligands for these receptors in rat rete testis fluid (RTF). Immunoblot analysis revealed that FGFRs 1-4 were present, and reverse transcription polymerase chain reaction (RT-PCR) analysis confirmed that both the IIIb and IIIc splice variants of FGFRs 1-3 were expressed. However, RT-PCR using RNA isolated from principal cells collected by laser capture microdissection revealed only FGFR-1 IIIc. Additional PCR analysis established that both the alpha and beta forms of FGFR-1 IIIc were expressed in principal cells. Both FGF-4 and FGF-8 were present in rat RTF, as determined by immunoblotting. Thus, FGF-2, -4, and -8, found in RTF, may act upon FGFR-1 IIIc in the principal cells of the initial segment to regulate GGT mRNA IV expression.

Animals↗
PubMed1986

Nonseminomatous germ cell tumor of the testicle: does extensive staging of the primary tumor predict the likelihood of metastatic disease?

To assess the hypothesis that local extent of the primary lesion in patients with nonseminomatous germ cell tumors of the testicle can predict disseminated disease, clinicopathological correlations of the primary tumor and metastases were determined in a retrospective review of 120 patients treated at our institution from 1970 to 1982. Pathological staging was available for all 93 patients with subdiaphragmatic disease and the primary tumor was examined by routine histological techniques in all cases. Increased primary tumor stage, as evidenced by invasion into the tunica vasculosa or extension into the rete testis, epididymis and/or lower or upper spermatic cord, was associated with metastatic disease in 91, 96, 97 and 97 per cent of the patients, respectively. Only 9 per cent of the patients with pathological stage A disease had vascular invasion compared to 45 and 67 per cent of those with stages B and C disease, respectively (p less than 0.01). Furthermore, metastases and/or eventual dissemination occurred in 84 per cent of the patients with clinical stage A disease and vascular invasion, and in only 23 per cent of those without vascular invasion (p less than 0.01). Size of the primary tumor was not of predictive value. Local extension of the primary lesion was common with embryonal carcinoma but it was not demonstrated when the predominant histological type was teratoma or teratocarcinoma, although metastases were present in 37 and 46 per cent of the latter cases, respectively. The implications of these findings, especially with regard to expectant management for clinical stage A nonseminomatous germ cell testis tumors, are discussed.

Adolescent↗
PubMedDate not supplied

Changes in vascular dynamics of the adult rat testis leading to transient accumulation of seminiferous tubule fluid after administration of a novel 5-hydroxytryptamine (5-HT) agonist.

The aim of the present study was to evaluate the possible mechanisms of testicular toxicity of GR40370X, a follow-up 5-hydroxytryptamine (5-HT) receptor agonist. Administration to adult male rats of a single (toxic) dose of 750 mg/kg GR40370X induced marked distension of seminiferous tubules and an associated increase in testis weight at 12-24 h with a gradual recovery to normal by 96 h. Seminiferous tubule distension was due to expansion of the lumen, which occurred at all stages of the spermatogenic cycle and was accompanied by vacuolation of the cytoplasm of elongating spermatids. Seminiferous tubule distension was preceded/accompanied by distension of the efferent ducts and rete testis with maximal changes evident at 24-48 h. These changes could not be explained by increases in seminiferous tubule fluid or interstitial fluid production, as both were reduced (15-20%), rather than increased, by treatment. Examination of the vasculature after treatment with 750 mg/kg GR40370X revealed significant changes that were maximal at 4 h and thus preceded rete/testicular changes. Veins of the mediastinal venous plexus, which overlies the rete, were constricted and arteriovenous anastomoses in the spermatic cord were shut/constricted, as determined (indirectly) by measurement of the dilution of outflowing testicular venous blood by incoming arterial blood. The latter effect of GR40370X could be blocked by co-administration of minoxidil, a vasodilator. Vascular effects of GR40370X had normalised by 24-48 h. It was also noted that administration of a toxic dose of GR40370X significantly lowered blood levels of LH and testosterone, though these changes were considered to be incidental and not involved in the other changes described above. None of the above changes were induced by a pharmacologically active dose (1 mg/kg) of GR40370X. It is concluded that the mechanism of testicular toxicity induced by 750 mg/kg GR40370X results from primary effects on the vasculature of the testis/neighbouring region, which in turn lead to impaired fluid resorption from the efferent ducts and rete and thence to accumulation of seminiferous tubule fluid in the rete and testis.

Animals↗
PubMed1997

Interactions between ovine cathepsin L, cystatin C and alpha 2-macroglobulin. Potential role in the genital tract.

The specific inhibitor of cysteine proteinases, cystatin C, was purified from ram rete testis fluid and the conditioned medium of Sertoli cells. This molecule associated with sheep liver cathepsin L at one of the fastest rates ever described for a proteinase/inhibitor interaction (1.75 +/- 0.20 x 10(8) M-1.s-1). But the association rate constant for the interaction of cathepsin L with alpha 2-macroglobulin, a non-specific inhibitor of proteinases, was also extremely high (8.8 +/- 0.75 x 10(6) M-1.s-1). Cathepsin L complexed with alpha 2-macroglobulin was protected from inhibition by type 2 and type 3 cystatins. The data indicate that cystatin C is the most potent inhibitor of cathepsin L in mammalian male genital tract fluids, whereas alpha 2-macroglobulin may act as a terminal acceptor of this enzyme. These inhibitors could therefore inhibit the activated form of procathepsin L which may appear during the complex process of spermatozoa production and maturation in the testis and epididymis.

Amino Acid Sequence↗
PubMed2001

Male germ cell transplantation: promise and problems.

Male germ cell transplantation is a novel technique in which donor male stem germ cells are surgically transferred to the seminiferous tubules of a recipient testis by direct injection or via the rete testis or efferent duct. All germ cells that are destined to become stem spermatogonia are defined as male stem germ cells, including primordial germ cells from the gonadal ridges, and gonocytes and stem spermatogonia from the testis, all of which are transplantable and capable of undergoing normal spermatogenesis. Xenotransplantation of male germ cells from one species into the testis of another species, including human testicular cells in the mouse, has so far proved to be unsuccessful. However, the immunodeficient mouse testis can support rat spermatogenesis and produce apparently normal rat spermatozoa. The underlying mechanisms remain elusive. The present mini-review will focus on the importance of stem spermatogonial transplantation for testicular stem cell biology and discuss the likelihood of immune rejection after transplantation, which may limit the success of all male germ cell transplantation.

Animals↗
PubMed1984

Localization of transferrin and transferrin receptors in rat testes.

One of the major proteins secreted by rat Sertoli cells in culture is a transferrin-like protein (Skinner and Griswold, 1980). The purpose of this study was to quantitate the amount of testicular transferrin in fluids isolated from the testis by the use of a radioimmunoassay and to determine the location of transferrin and transferrin receptors in the testis by indirect immunofluorescence. Seminiferous tubule fluid, rete testis fluid, and testicular lymph were collected from rat testes and were found to contain 141 micrograms, 47 micrograms and 3.7 mg transferrin per ml of fluid, respectively. Serum was found to contain 3.7 mg/ml transferrin. Paraffin sections of rat testis were incubated with rabbit anti-rat transferrin, biotinylated goat anti-rabbit and fluorescein-conjugated avidin. Immunoreactive transferrin was thus localized on the proacrosome and nuclear cap of developing spermatids. Late spermatids showed transferrin over the entire region of the head but mature testicular spermatozoa exhibited little fluorescence. The interstitial tissue between seminiferous tubules fluoresced brightly, indicating a large amount of transferrin in this area. By pretreating sections with rat transferrin, the receptor for the protein was localized on and in spermatocytes and early round spermatids. Dividing germ cells were brightly fluorescent.

Animals↗
PubMed1995

Organ preserving surgery of malignant germ cell tumors.

If a tumor arises in a solitary testis the patient loses fertility and requires lifelong androgen substitution. We describe the technique and results of organ preserving enucleation resection performed in 14 patients. The tumor was excised under (cold) ischemia via a mini-surgical technique using 2-fold magnification and blood vessels were localized intraoperatively by Doppler sonography. The procedure was successful in 10 of 14 patients. In 2 patients the organ required ablation later because of insufficient blood supply. Two patients had subnormal testosterone levels after treatment. There were no local recurrences. Prerequisites for this type of treatment are detailed knowledge of the vascular anatomy of the testis, tumor not too close to the rete testis, largest diameter 20 mm. or less, normal preoperative plasma testosterone level, postoperative local irradiation with 20 Gy., followup biopsies and hormonal status obtained 6 months after enucleation resection, and meticulous followup for early detection of local recurrences or systemic progression.

Adult↗
PubMed1998

Regulation of gamma-glutamyl transpeptidase catalytic activity and protein level in the initial segment of the rat epididymis by testicular factors: role of basic fibroblast growth factor.

The objective of this study was to test the hypothesis that gamma-glutamyl transpeptidase (GGT) catalytic activity and protein level in the initial segment are regulated by testicular factors. In the rat epididymis, levels of GGT catalytic activity were initial segment > caput > corpus = cauda. GGT catalytic activity and protein level in the initial segment decreased after efferent duct ligation (EDL) for 3 days, but were recovered when initial segment pieces were incubated with ovine or rat rete testis fluid (oRTF or rRTF, respectively). Factors responsible for the recovery were shown to be greater than 10 kDa and protein-like, but these factors were not androgen-binding protein or testosterone in oRTF. Further experiments were designed to test the hypothesis that growth factors within oRTF and rRTF regulate GGT catalytic activity and GGT protein level. Basic fibroblast growth factor (bFGF) but not epidermal growth factor recovered GGT catalytic activity and protein level in the initial segment following 3-day EDL. Western blot analyses also revealed that bFGF-like proteins were present in rRTF, epididymal luminal fluid, and rat initial segment homogenate, and that the level of bFGF-like proteins declined in the initial segment following 3-day EDL. Using a bFGF monoclonal antibody, a small amount of bFGF-like proteins was found to be also present in oRTF. Our studies suggest that bFGF is one of the testicular factors involved in the regulation of epididymal GGT catalytic activity and protein level. Since decreased GGT catalytic activity caused by 3-day EDL in the rat initial segment was also recovered by a tumor promoter, phorbol 12-O-tetradecanoylphorbol 13-acetate, it is possible that a signal transduction pathway is involved in the regulation of GGT catalytic activity and GGT protein level by testicular factors. Western blot analyses also indicated that the 43-kDa bFGF-like protein in the lumen of the rat epididymis originates from the testis, is concentrated in the initial segment, and is reabsorbed by the epididymal epithelia from proximal to distal epididymal regions.

Animals↗