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At least 685 records · Page 38Linked to original sources
PubMed2006

Can inhibin-B predict the outcome of microsurgical epididymal sperm aspiration in patients with suspected primary obstructive azoospermia.

AIM: To evaluate whether inhibin-B can predict the outcome of a microsurgical epidymal sperm aspiration (MESA) procedure in patients with suspected primary obstructive azoospermia (OA) and if inhibin-B can replace testicular biopsy in the diagnostic work-up of these patients. METHODS: Inhibin-B levels and testicular biopsy scores were related to the outcome of MESA in 43 patients with suspected primary OA. MESA was considered to be successful when epididymal sperm could be identified during the procedure. RESULTS: Spermatozoa were present in the epididymal aspirate in 28 out of the 43 patients (65%). Inhibin-B values were not significantly different in patients with successful or unsuccessful MESA. The modified Johnsen score, however, was significantly lower in patients with unsuccessful MESA (P = 0.003). A rete testis obstruction or epididymal malfunctioning was found in 15% of patients with suspected primary OA, reflected by unsuccessful MESA despite normal inhibin-B levels and normal testicular histology. CONCLUSION: Inhibin-B cannot replace testicular biopsy as a diagnostic tool in the work-up of patients with suspected primary OA. Testicular biopsy is useful in identifying patients with spermatogenic arrest, who might have normal inhibin-B values.

Azoospermia↗
PubMed2002

New light shed on fluid formation in the seminiferous tubules of the rat.

In this study the effects of perfusing isolated seminiferous tubules of the testes are reported for the first time. Initial perfusion studies (fast rate perfusion) resulted in gross morphological damage to the seminiferous tubules. The recorded transepithelial potential (V(t)) was close to 0 mV. Slow perfusion rates eliminated morphological damage to the perfused tubules. These tubules exhibited a V(t) of -5.4 +/- 1.8 mV which was significantly different (P < 0.0001) from tubules that were perfused at a fast rate. Additional non-perfusion electrophysiological experiments (oil-gap and agar probe techniques) provided the confirmation that tubules not morphologically compromised produced a higher V(t) which was not statistically different (P < 0.0001) from slowly perfused tubules. A revised hypothesis on fluid secretion is postulated. In brief, that the seminiferous tubule is solely responsible for the production of its luminal fluid. This hypothesis is contrary to the long standing 'Tuck' hypothesis which suggested that the source of luminal fluid in the seminiferous tubule originated from secretions of Sertoli cells as well as from distal testicular structures, e.g. the rete testis.

Aerobiosis↗
PubMed1994

Secondary oxalosis and sperm granuloma of the epididymis.

A 30 year old man with a 20 year history of chronic renal failure who presented with a testicular lesion is described. The lesional pathology, secondary oxalosis, and associated sperm granuloma of the epididymis was clinically considered to be an intrascrotal tumour. The oxalate crystal deposition was present within the rete testis, the ductuli efferents, and the epididymis along with sperm granulomata. This seems to be a rare complication of secondary oxalosis associated with chronic renal failure and having both clinical and pathological implications.

Adult↗
PubMed1988

Testicular cysts: differentiation with US and clinical findings.

In 34 of 847 patients (4%), testicular cysts were discovered with high-resolution ultrasound (US). Sixteen had a cystic testicular tumor, and US images showed multiple cysts and solid tumor portions in 12 of these 16 (75%). Eighteen patients had nonneoplastic cysts: Five had cysts of the tunica albuginea, and 13 had intratesticular cysts. All tunica albuginea cysts were palpable as small masses, and only US images showed that the masses were cystic. None of the 13 intratesticular cysts was palpable; all were accidentally discovered with US, which showed that 12 were single cysts with a marginal location (92%). On histologic studies, the nonneoplastic cysts were related to the spermatic ducts (rete testis, efferent ductules) and frequently appeared as postinflammatory alterations. Only five patients with intratesticular cysts were followed up with US, and no changes occurred. The combination of clinical and US findings facilitated the differentiation between nonneoplastic and neoplastic testicular cysts.

Adolescent↗
PubMed1989

Co-existence of gametic and agametic seminiferous tubules in a chimeric mouse. A light- and electron-microscopic study.

Six chimeras, including 4 phenotypic males and 2 females, were produced by aggregation of F1 (C57BL x BALB/c) and Swiss white embryos. All were fertile, except 1 male, whose deviation in testicular structure prompted this light- and electron-microscopic study. This chimera had a well-developed sperm-conducting system, sperm in the epididymis and active accessory sex glands. The testes displayed typical parenchymal and stromal components with the important exception of co-existence of gametic and agametic seminiferous tubules. These tubules were organized in territories of quasi-lobular configurations which appeared to open separately into rete testis. The former corresponded to normally developed and active seminiferous tubules, while the latter were solid testicular cords devoid of any germ cells and embedded in solid masses of interstitial (Leydig) cells. Special mitochondrial transformations were identified in sustentacular (Sertoli) cells of both types of tubules, in maturing spermatids and sperm. These and other submicroscopic sperm defects might be the cause of infertility.

Animals↗
PubMed1994

Seminal carnitine concentration in obstructive azoospermia.

Seminal carnitine levels were studied in 67 patients with obstructive azoospermia. In 25 patients a bilateral vasectomy had been performed previously and for refertilization a vasovasostomy was performed. In the remaining 42 men the occlusion was located within the epididymis. In postvasectomy cases and when the occlusion was located in the cauda epididymidis, carnitine concentrations were low with mean values of 114.57 and 122.44 mumol/l respectively. When the occlusion was in the region of the corpus the mean value of seminal carnitine increased to 192.56 mumol/l, and when the occlusion was found in the caput or the rete testis the mean value amounted to 417.20 mumol/l (normal mean levels of carnitine in normospermic patients 440-990 mumol/l). After successful vasovasostomy, free carnitine levels returned to the normal range of 510.82 mumol/l. These results indicate a highly significant correlation between seminal carnitine concentrations and the anatomic site of occlusion of the epididymis.

Carnitine↗
PubMed1986

Heterogeneity of basement membranes of the human genitourinary tract revealed by sequential immunofluorescence staining with monoclonal antibodies to laminin.

We used monoclonal antibodies specific for human laminin to analyze immunohistochemically the heterogeneity of the basement membranes in various parts of the genitourinary tract. By indirect immunofluorescence microscopy we show that antibody 3H11 reacts with all epithelial basement membranes in the kidneys, testes, epididymis, prostate, uterus, oviduct, and ovary, as well as the smooth muscle cells, blood vessels, and nerves. Antibody 4E10 reacted with most epithelial basement membranes in these organs but was unreactive with the basement membranes of peripheral glomerular capillary loops and the basement membranes of the oviductal mucosa, seminiferous tubules, straight tubules, and rete testis. Hilar seminiferous tubules were reactive with 4E10. In contrast to 3H11, which reacted with all vascular, subendothelial, and muscular basement membranes, 4E10 reacted only with the subendothelial basement membrane of capillaries and veins. The difference in the distribution of epitopes could be demonstrated in tissue sections sequentially reacted with two monoclonal antibodies, but only if the antibody of restricted reactivity (4E10) was used first. These data show that the heterogeneous expression of distinct epitopes of laminin in basement membranes can be demonstrated in the same tissue section by sequential staining. This heterogeneity of basement membranes most likely reflects conformational differences in the expression of epitopes on the laminin molecule in various anatomic structures.

Adult↗
PubMed1986

Prognostic factors in stage I non-seminomatous germ-cell testicular tumors managed by orchiectomy and surveillance: implications for adjuvant chemotherapy.

Between February 1979 and March 1985, 126 patients with clinical stage I non-seminomatous germ-cell testicular tumors were entered into a surveillance study after orchiectomy. Of this group, 36 (28%) have relapsed. The prognostic significance of 13 clinical, histopathologic, and biochemical factors has been analyzed. Vascular invasion and lymphatic invasion (LI) within the primary tumor, histology, and involvement of the epididymis and rete testis were significantly associated with an increased risk of relapse. However, multiple regression analysis showed that only histology and LI were significant, independent prognostic factors. These findings provide the basis for the consideration of adjuvant chemotherapy for patients with apparent clinical stage I testicular non-seminoma who are at high risk of harboring occult metastases.

Adult↗
PubMed1988

Stage I nonseminomatous germ cell testicular tumor: prediction of metastatic potential by primary histopathology.

A study of 60 patients with clinical stage I nonseminomatous germ cell testicular tumor (NSGCT) was conducted to identify prognostic factors that may predict the likelihood of metastasis. Clinical features and histopathologic features of the primary testicular tumor were examined and analyzed for correlations with the presence of retroperitoneal nodal metastasis documented by surgery (N+) and with development of relapse (R+). Pathologic tumor stage greater than or equal to 2, with tumor extension into the tunica albuginea, rete testis, epididymis, or spermatic cord, was correlated with an increased rate of N+ compared with pathologic tumor stage I (P = .001). Vascular invasion was correlated with a higher rate of N+ (P = .05) and had a similar association with R+ (P = .08). Tumors containing less than 50% teratoma were found to have a higher rate of N+ than tumors with greater than or equal to 50% teratoma (P = .02). Based on the identified prognostic factors, a model for predicting the probability of retroperitoneal nodal metastasis in clinical stage I patients is proposed. The risk factors for nodal metastasis are: pathologic tumor stage greater than or equal to 2, vascular invasion, and less than 50% teratoma. Patients with none of the risk factors are considered at low risk and may be offered orchiectomy alone with surveillance for initial treatment. Patients with all three risk factors are at high risk and should be treated with a retroperitoneal lymph node dissection (RPLND) or possibly chemotherapy. Patients with one or two risk factors are at intermediate risk; it is recommended that they undergo RPLND. This risk model facilitates a rational approach to the management of clinical stage I NSGCT.

Adult↗
PubMed1981

Evidence for a hypothalamic site of action of inhibin to suppress FSH release.

To determine if inhibin has a hypothalamic site of action to suppress FSH release, highly purified inhibin preparations from the rete testis fluid (RTF) of rams were injected into adult male rats which had been orchidectomized (ORDX) 24 hours earlier. Third ventricular (3rd V) injection of a potent inhibin fraction (RTF 38-I) significantly depressed plasma FSH concentrations, without influencing LH, 4-10 h after treatment. A less active preparation of inhibin (RTF 38-II) at the same dose had no effect. A higher dose of another less potent fraction (RTF 1A) significantly reduced FSH 2-6 h following 3rd V administration, accompanied by slight but significant decrements in LH at 2 and 4 only. To determine responsiveness of the pituitary, luteinizing hormone-releasing hormone (LHRH) was injected intravenously at 6 h. It induced similar elevations of FSH and LH in inhibin- and saline-treated groups. Systemic administration of RTF 38-II at a dose 2.5-fold higher than the dose effective centrally failed to modify either FSH or LH levels up to 6 h. These results provide evidence that inhibin from the male can preferentially suppress FSH release by a CNS site of action in addition to its well-known pituitary site of action.

Animals↗
PubMed1986

Measurement of a follicle-stimulating hormone-responsive protein of Sertoli cell origin using an enzyme-linked immunoblot assay.

Many proteins secreted by Sertoli cell-enriched cultures are maximally stimulated by a combination of FSH and testosterone. Since very few are stimulated primarily by FSH, we thought it pertinent to identify such proteins. Sertoli cell-enriched cultures were prepared from testes of 20-day-old rats and grown in serum-free medium containing insulin, transferrin, and epidermal growth factor and in such medium supplemented with FSH, testosterone, or FSH plus testosterone. Media were fractionated using HPLC, and proteins were identified by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. A protein designated CMB-2, with an apparent mol wt of 22,000, was shown to increase in response to FSH. Antiserum was raised using denatured protein eluted from SDS-polyacrylamide gels as the antigen, and a specific immunoassay using a combination of SDS-polyacrylamide gel electrophoresis and Western blotting was developed. The production of CMB-2 by primary Sertoli cell-enriched cultures was found to increase in a dose-dependent manner in response to FSH (30-1000 ng/ml); secretion was not significantly affected by testosterone (2 X 10(-13) M). An investigation of the tissue distribution of CMB-2 showed that the puberty, CMB-2 is secreted into the rete testis and accumulates in the epididymis in high concentration. We conclude that CMB-2 will be a useful marker to study the action of FSH on the rat testis.

Androgen-Binding Protein↗
PubMed1990

Oxytocin in the ovine ductuli efferentes and caput epididymidis: immunolocalization and endocytosis from the luminal fluid.

The presence, possible biosynthesis, and uptake of oxytocin from luminal fluid in the ductuli efferentes and caput epididymidis of the ram were studied. Specific immunostaining for oxytocin, but not neurophysin, was observed in the ductuli efferentes as well as caput epididymidis. This indicates the presence, but not production, of oxytocin in epithelial cells of these ducts. Staining was predominantly present in the epithelium, especially in the middle lobules of the ductuli efferentes and initial segment of the epididymis. Endocytosis of oxytocin was studied by electron microscopy after intraluminal microinjections of oxytocin conjugated to colloidal gold (8-10 nm), a 20-fold excess of oxytocin followed by oxytocin-gold, or plain colloidal gold into the ductuli efferentes and four successive regions of the caput epididymidis. Specific uptake by a receptor-mediated process was evidenced by the presence of more gold particles within epithelial cells after oxytocin-gold injections than after control injections. The quantity of oxytocin-gold endocytosed was 3.7-fold greater in the ductuli efferentes than in the initial segment of the epididymis. Within the caput epididymidis, more oxytocin-gold was endocytosed in the initial segment and proximal caput epididymidis than in two distal regions. We conclude that localization of oxytocin in epithelia of the excurrent ducts is a consequence of endocytosis (predominantly receptor mediated) of luminal oxytocin entering in rete testis fluid; however, uptake of blood-borne oxytocin cannot be excluded. Although oxytocin may have a role in sperm transport via action on smooth muscle in the ductal wall, the regional pattern of endocytosis of oxytocin is suggestive of a role for oxytocin in epithelial function in the ductuli efferentes and proximal portions of the caput epididymidis.

Animals↗
PubMed1993

Nuclear localization of the protein encoded by the Wilms' tumor gene WT1 in embryonic and adult tissues.

The human Wilms' tumor gene WT1 encodes a putative transcription factor implicated in tumorigenesis and in specifying normal urogenital development. We have studied the distribution of WT1 protein and mRNA using immunohistochemistry and in situ hybridization. Monoclonal antibodies were raised against a peptide specific to the first alternative splice site of WT1. Two antibodies specifically reacted on Western blot to this WT1 isoform. Immunofluorescence localized WT1 protein to podocytes during mesonephric and metanephric development. In situ hybridization revealed a similar pattern of expression except that WT1 mRNA was also present in metanephric blastema and renal vesicles. Messenger RNA expression was most pronounced in the kidneys during early fetal development and declined thereafter. In contrast, WT1 protein was readily detectable in glomerular podocytes throughout adulthood. WT1 protein in Wilms' tumor was present in blastema and glomeruloid structures. Expression in the female gonad was linked to the different stages of granulosa cell development. In the male gonad, expression was restricted to Sertoli cells and their precursors, the embryonic tunica albuginea and the rete testis. The intracellular distribution of the WT1 protein was investigated by confocal laser microscopy and was demonstrated to be exclusively nuclear. The nuclear distribution and the selective pattern of expression support the proposed role of WT1 as a transcription factor active during urogenital development. The persistence of WT1 expression in the adult kidney suggests a role in homeostasis of the podocyte.

Blotting, Western↗
PubMed2006

DAX1 and X-linked adrenal hypoplasia congenita: clinical and molecular analysis in five patients.

OBJECTIVE: Mutations in the gene coding for the orphan nuclear receptor DAX1 cause X-linked adrenal hypoplasia congenita (AHC). Affected boys usually present with primary adrenal failure in early infancy or childhood. Impaired sexual development due to hypogonadotropic hypogonadism becomes manifest at the time of puberty. Moreover, evidence from Dax1 knockout mice and a limited number of patients with AHC, suggests that mutations in DAX1 may directly cause abnormalities in spermatogenesis. The aim of this study was to characterize clinically and genetically five patients with AHC. DESIGN: DNA sequencing analysis, endocrine testing, testicular ultrasound and semen analysis with 1-year follow-up after gonadotropin treatment. METHODS: We report on five men with classic AHC manifestations. Genomic DNA was extracted from patients' peripheral blood leukocytes and the coding region, splice sites, and promoter (-240 bp) region of DAX1 were directly sequenced. RESULTS: Three known and two novel mutations were detected in the DAX1 coding sequence in these patients. Semen analysis was performed in four of the five patients and showed azoospermia. Twelve-month treatment with gonadotropins did not restore fertility in these patients. All patients showed a normal testicular Doppler ultrasound, in contrast with that observed in Dax1-deficient mice, which display abnormalities in the rete testis. CONCLUSIONS: These cases further expand the number of DAX1 mutations reported in the literature, as well as our clinical knowledge of this rare disease.

Adolescent↗
PubMed1979

Effects of osmolality, bicarbonate and buffer on the metabolism and motility of testicular, epididymal and ejaculated spermatozoa of boars.

Spermatozoa were collected from the rete testis of conscious boars, from the cauda epididymidis by retro-flushing, and by ejaculation. Testicular spermatozoa showed no progressive motility, and that of ejaculated was greater than that of epididymal spermatozoa. Glycolysis and respiration of testicular spermatozoa, while lower than that of the more mature cells, were only slightly affected by the incubation conditions. Epididymal spermatozoa converted 83% of the glucose they utilized to CO2 or lactate, but testicular cells converted only 35% to these metabolites. Synthesis of lipid was greatest by testicular spermatozoa. With the more mature cells hyperosmolar conditions depressed CO2 production, but increased lactate production, and these changes were greater for ejaculated than for epididymal spermatozoa. Glycolysis plus respiration of these cells was related to their motility. These results were interpreted as showing increasing motility, glycolysis and respiration with maturation, but also decreased synthetic capacity and increased sensitivity to the environment.

Acid-Base Equilibrium↗
PubMed1979

Factors affecting the entry of testosterone into the lumen of the cauda epididymidis of the anaesthetized rat.

When [3H]testosterone was infused into the general circulation of the rat, perfusion of a length of the cauda epididymidis (17 +/- 1.0 (s.e.m.) cm, n = 36) with perfusates of varied composition revealed a low entry of radioactivity (1--10% plasma levels; 10 exps) with protein-free perfusates, and a greater entry (15--48%; 10 exps) when the perfusate contained bovine serum albumin (38 mg/ml). When the perfusate contained ovine or rat testicular fluid, or rat epididymal fluid at protein concentrations of 3 mg/ml or less, the entry of radioactivity into the epididymis was greater than when the perfusate contained 3 mg BSA/ml. The addition of ovine rete testis fluid protein (3 mg/ml to BSA (38 mg/ml) in the perfusate increased the uptake of radioactivity (58--106%; 6 exps). Radioactivity in blood was principally associated with testosterone (90, 95% total blood activity, 2 rats), whereas both [3H]testosterone (37, 41% total perfusate activity) and [3H]dihydrotestosterone (42, 63% total perfusate activity) was present in BSA-containing perfusates. The proportion of dihydrotestosterone appeared to increase when the perfusate contained protein of testicular origin.

Animals↗
PubMed1979

Biochemical and physiological studies of androgen-binding protein in the reproductive tract of the ram.

The electrophoretic mobility, effect of pronase, temperature stability, affinity constant and specificity of androgen-binding protein (ABP) were compared in rete testis fluid (RTF), cauda epididymal plasma (CEP) and seminal plasma (SP) of the ram in which the levels of ABP, dihydrotestosterone (DHT), total protein and the number of spermatozoa were also measured. The characteristics of the ABP appeared to be almost identical in all 3 fluids. ABP was highly concentrated in the cauda epididymidis although 50-75% of it was utilized or destroyed during transit through the epididymis. The levels of ABP were higher in the breeding season and positively correlated with DHT in RTF and SP. It is concluded that ABP might be responsible for the increase in DHT in the reproductive tract of the ram during the breeding season and that ABP in the SP might serve as a useful marker of Sertoli cell function in the ram.

Androgen-Binding Protein↗
PubMed1983

Spermiogram and sperm reserves in hybrid Bos indicus X Bos taurus bulls after scrotal insulation.

Scrotal insulation for 48 h raised subcutaneous scrotal temperature by 4 degrees C in hybrid Bos indicus X Bos taurus bulls. The incidence of decapitated spermatozoa in the ejaculate increased significantly between 6 and 14 days and that of protoplasmic droplets and tail abnormalities between 20 and 23 days after insulation, respectively. Simultaneously, the percentages of spermatozoa with lost and damaged acrosomes increased significantly 12-17 days after insulation. At slaughter 23 days after scrotal insulation sperm production rates and gonadal reserves had not been affected by insulation, but epididymal reserves were markedly reduced, particularly in the cauda. Elevated testicular temperature therefore had an effect on immature spermatozoa in the caput epididymidis and on spermatids, but it is suggested that selective sperm resorption in the rete testis and excurrent ducts may prevent some of these changes being expressed in the ejaculate.

Animals↗