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PubMed1989

Identification of the cytochrome P-450 isozymes responsible for testosterone oxidation in rat lung, kidney, and testis: evidence that cytochrome P-450a (P450IIA1) is the physiologically important testosterone 7 alpha-hydroxylase in rat testis.

Previous studies have shown that several forms of cytochrome P-450 present in rat liver microsomes oxidize testosterone with a high degree of regio- and stereospecificity. The aim of this study was to characterize the pathways of testosterone oxidation catalyzed by rat extrahepatic microsomes. Lung, kidney, testis, prostate, and brain were isolated from 3- and 14-week-old-male Sprague-Dawley rats. Microsomes from lung, kidney, and testis catalyzed distinctly different pathways of testosterone oxidation, whereas microsomes from prostate and brain failed to hydroxylate testosterone directly in a time- and protein-dependent manner. Lung microsomes from immature and mature rats converted testosterone to 16 alpha-hydroxytestosterone, 16 beta-hydroxytestosterone, and androstenedione. Lung microsomes were shown by Western immunoblot to contain cytochrome P-450b (P450IIB1), which has been shown previously to catalyze these three pathways of testosterone oxidation. Antibody against cytochrome P-450b strongly inhibited (greater than 80%) androstenedione formation and completely inhibited (greater than 95%) the 16 alpha- and 16 beta-hydroxylation of testosterone catalyzed by lung microsomes (as did carbon monoxide and antibody against NADPH-cytochrome P-450 reductase). Kidney microsomes from mature male rats converted testosterone to 2 alpha-hydroxytestosterone, 16 alpha-hydroxytestosterone, and androstenedione, whereas only the latter pathway was catalyzed by kidney microsomes from immature rats. Kidney microsomes from mature male rats were shown by Western immunoblot to contain cytochrome P-450h (P450IIC11), which has been shown previously to convert testosterone to 2 alpha-hydroxytestosterone, 16 alpha-hydroxytestosterone, and androstenedione. Antibody against cytochrome P-450h completely inhibited (greater than 95%) the 2 alpha- and 16 alpha-hydroxylation of testosterone by kidney microsomes, but had little effect on androstenedione formation, which is catalyzed by 17 beta-hydroxysteroid dehydrogenase. Testicular microsomes from mature, but not immature, rats catalyzed the 7 alpha-hydroxylation of testosterone. Previous studies have shown that this reaction is catalyzed in liver microsomes by cytochrome P-450a (P450IIA1). Testicular microsomes from mature, but not immature, rats were shown by Western immunoblot to contain cytochrome P-450a. Antibody against cytochrome P-450a or NADPH-cytochrome P-450 reductase completely inhibited (greater than 95%) the 7 alpha-hydroxylation of testosterone by testicular microsomes. A 90:10 atmosphere of carbon monoxide and oxygen did not appreciably block the 7 alpha-hydroxylation of testosterone by testicular microsomes, wh

Animals↗
PubMed1983

Studies of the human testis. XVIII. Simultaneous measurement of nine intratesticular steroids: evidence for reduced mitochondrial function in testis of elderly men.

To determine the basis for the decline in testosterone production by the aged testis, intratesticular unconjugated steroids, including testosterone, pregnenolone (3 beta-hydroxy-5-pregnen-20-one), 17 alpha-hydroxypregnenolone (3 beta,17 alpha-dihydroxy-5-pregnen-20-one), dehydroepiandrosterone (3 beta-hydroxy-5-androsten-17-one), androstenediol (5-androstene-3 beta,17 beta-diol), progesterone, 17 alpha-hydroxyprogesterone, androstenedione (4-androstene-3,17-dione), and 17 beta-estradiol, were measured by simultaneous RIAs in 32 previously untreated elderly men (aged 61-85 yr) undergoing orchiectomy as therapy for prostatic carcinoma and 20 young men (aged 25-35 yr) with oligospermia and varicocele. In vitro steroidogenesis using labeled pregnenolone as substrate was also investigated. Serum and intratesticular testosterone levels were lower (P less than 0.05) in aged patients [3.3 +/- 1.9 ng/ml and 0.86 +/- 0.53 microgram/g tissue (mean +/- SD)] than in young men (6.4 +/- 1.9 ng/ml and 1.7 +/- 1.1 microgram/g tissue), while circulating LH levels were higher (P less than 0.05) in elderly men (151 +/- 105 ng/ml) than in the young men (79 +/- 33 ng/ml), indicating that a primary pathological process affects the senescent testis, producing a decline in testosterone production. Study of bioconversion of [3H]pregnenolone to delta 4 steroids, 17 alpha-hydroxysteroids, and C19 steroids as well as analysis of the relative amounts of intratesticular steroids, as determined by RIA, revealed no apparent differences in the process of microsomal steroidogenesis in elderly compared to that in young men. The sum of the nine measured intratesticular steroid concentrations per g tissue wt was significantly lower (P less than 0.05) in aged patients (1.94 +/- 0.93 microgram/g tissue), than in young patients (3.68 +/- 1.90 micrograms/g tissue). The sum of the nine intratesticular steroids measured was positively correlated (P less than 0.01) with circulating LH levels in both patient groups, and the slope of this regression line was 14-fold greater for young men than for elderly men. Since the total concentration of the nine measured steroids reflects the pregnenolone supplied by the mitochondria within Leydig cells, it appears that the decline in Leydig cell function in aged men is attributable to a reduced supply of mitochondrial steroid precursors rather than to an impairment in microsomal steroidogenesis.

Adult↗
PubMedDate not supplied

[Morphologic and histoenzymologic analysis of effect of electrical fields at 17 khz on testis and testis appendages in mice].

Methods of quantitative morphological and histochemical assay were used to study effects of 9-month electrical exposure (f = 17 kHz, E = 100 kW/m2 for 1 or 4 hrs, 5 d/w) on testis and testis appendages in mice. Exposure in electromagnetic field gave rise to desquamation of spermatogenic epithelial layers in the seminiferous tubes, reduction of the number of testosterone-producing cells, microcirculatory changes, metabolic rearrangements, principally compensatory by nature and aimed to maintain spermatogenesis and steroidogenesis. Results of the experiment suggest accelerated reproductive ageing.

Adaptation, Physiological↗
PubMed1997

Testis sparing surgery for epidermoid cyst of the testis: a case report.

A rare tumour of a prepubertal child, an epidermoid cyst, was excised with testicular preservation. Childhood testicular tumours are usually benign. Although epidermoid cysts of the testis may have teratomatous component, testicular teratomas are generally benign in the prepubertal child. For these reasons testis sparing surgery seems applicable in childhood epidermoid cysts.

Child↗
PubMed1993

Testis sparing surgery for pediatric epidermoid cysts of the testis.

Epidermoid cyst of the testis is a rare, benign intratesticular tumor in children. Four patients 4 to 15 years old with epidermoid cysts were managed by tumor excision with salvage of the testis. Preoperative ultrasound, tumor marker status and intraoperative findings were suggestive of a benign neoplasm. Under these circumstances epidermoid cysts may be safely treated by excision in prepubertal patients.

Adolescent↗
PubMed1994

A new case of malignant mesothelioma of the tunica vaginalis testis. Immunohistochemistry in comparison with an adenomatoid tumor of the testis.

Malignant mesothelioma of the tunica vaginalis testis is an extremely rare tumor with 41 previously reported cases. The histological and immunohistological features of a new case in an 80-year-old patient are described and compared with an adenomatoid tumor of the tunica vaginalis testis, which is considered to be the benign variant of malignant mesothelioma. Both tumors revealed strong cytoplasmic staining for a panepithelial antibody (Lu-5) and membranous staining for BMA-120 (a mesothelial/endothelial cell marker) but yielded negative staining results with the endothelial cell markers QBend-10 (CD 34), Factor VIII-related antigen (vWF) and UEA-1. There was also negative staining for CEA, Ber-EP4, HEA-125 and Blood group related antigens A, B, H. An identical staining pattern was evident in normal and reactive mesothelial cells. Our data support a mesothelial rather than an endothelial derivation of the adenomatoid tumor studied.

Aged↗
PubMed1997

The reproductive imperative: a case report highlighting the possibility of using chemotherapy to conserve the testis in patients with testis cancer.

This report examines the dilemma that a patient, who was a doctor, faced on discovering that he was developing a second primary testicular tumour (seminoma) in a solitary testis. The usual treatment for this is radical orchidectomy. He rejected this on the grounds that he wanted to have children, and eventually decided on the use of single-agent carboplatin chemotherapy. Seventeen months after treatment, there was no evidence of tumour on MRI or ultrasound scanning and there is some recovery of spermatogenesis. So far, 13 of 14 patients treated with chemotherapy for metastatic disease (with the primary tumour being left in situ), which has normalized following treatment, have survived for more than 5 years without evidence of tumour recurrence. This approach could be a viable option for men with tumours in a solitary testis who have not completed their families. However, a larger prospective study is essential to determine whether this approach is safe, so that these patients will not have to bear the psychological burden of choosing between their chances of survival and the possibility of fathering children.

Adult↗
PubMed1994

Carcinoma in situ of the testis followed by an overt malignant teratoma of the testis within 12 months.

A case of bilateral metachronous testicular non-seminomatous germ cell tumour (NSGCT) is presented. The second tumour was preceded by carcinoma in situ, diagnosed at the time of the first orchidectomy. The patient was placed under active surveillance and 1 year later the second testis tumour developed. A second orchidectomy was performed and testosterone replacement begun. Carcinoma in situ of the testis is discussed.

Adult↗
PubMed1993

Testis tumor: the problem of the undescended testis.

The increased incidence of testicular cancer occurring in the undescended testis is well documented. Ten to 12% of cryptorchid testes are demonstrated in all series of testicular cancer which is in keeping with a 4 to 10 times increase of the risk. A lot of work is being carried out to elucidate the etiological factors that could explain this increase. A common etiological endocrine factor might be implicated. As it is well known that orchidopexy does not prevent subsequent malignancy, its effects on the histology of the testis and tumor pattern is studied with consideration of age at orchidopexy. Carcinoma in situ (Cis) first discovered in the infertile male population and seen many years before invasive cancer may provide a useful tool for follow-up of cryptorchid patients. According to the results of this work, management of cryptorchid testes is planned as either orchidopexy or orchidectomy, and time and place for biopsies is decided. Life-long follow-up is advocated.

Adult↗
PubMed1993

Testis-sparing surgery for benign lesions of the prepubertal testis.

Testis tumors in children are more likely to be benign that those in adults, and those tumors that are malignant are associated with a much lower incidence of metastases. As a result, a less-aggressive surgical approach to pediatric lesions has evolved. A testis-sparing operation in appropriate cases has potential psychological and cosmetic advantages for the developing child, and there may be functional advantages for fertility when the child matures.

Child↗
PubMedDate not supplied

On the morphology of the transitional zones from the rete testis into the ductuli efferentes and from the ductuli efferentes into the ductus epididymidis. Investigations on the human testis and epididymis.

Transitions from the rete testis into the ductuli efferentes and from the ductuli efferentes into the ductus epididymidis were examined in the epididymes of 4 patients with prostatic cancer aged 65, 72, 77 and 78 years, in the epididymis of a 19 year-old accident victim and in the epididymis of an embryo of the 12th week. Concerning the former area, the results published up to now were confirmed. But according to our examinations, the transition from the ductuli efferentes into the ductus epididymidis is different from what has been described in the literature so far. In the adult human, the ductuli efferentes do not show end-to-side connections with the ductus epididymidis, but end-to-end junctions with "extensions" of the ductus epididymidis which finally join the ductus epididymidis end-to-side. However, in the epididymis of the embryo, one still finds end-to-side connections of ductuli efferentes and the ductus epididymidis. It was concluded that the extensions of the ductus epididymidis are formed during the development of the system of canaliculi in the epididymis from the embryonal stage to adult age.

Adult↗
PubMed1989

Testis-specific histone H1t is truly a testis-specific variant and not a meiotic-specific variant.

Immunoblotting studies using highly specific polyclonal anti-histone H1t-IgG, which was extensively characterized by us previously, did not produce a signal with any of the histone H1 subtypes of either 1-day-old or adult rat ovarian nuclei. The absence of histone H1t in ovarian nuclei was also confirmed by indirect immunofluorescence studies. It is concluded, therefore, that histone H1t is truly a testis-specific histone variant and not a meiotic-specific variant.

Animals↗
PubMed1994

Dynamic magnetic resonance imaging of the contralateral testis in patients with malignant tumor of the testis.

OBJECTIVES: Dynamic magnetic resonance imaging (MRI) was tested using a dynamic technique to evaluate the possibility of differentiating between normal contralateral testes and testes with a carcinoma in situ. METHODS: Since March 1990, 20 volunteers and 21 patients with a malignant tumor of the testis were examined in a field strength of 1.5 Tesla (Philips Gyroscan S15) with a multislice T1-weighted fast field echo sequence before and every 63 seconds after the injection of 0.1 mmol/kg gadolinium-diethylenetriamine pentaacetic acid. RESULTS: Significant differences (p < 0.001) in signal changes of contralateral testes were detected in dynamic MRI. This increased signal enhancement is detected even 45 months after orchiectomy in the contralateral testes. The signal increase is reduced in follow-up controls. These observations are explained by an increased perfusion which seems to be induced after a postoperative irritation, an unspecific inflammation, or postoperative bleeding. CONCLUSIONS: To avoid false-positive diagnoses of tumors or carcinomata in situ in contralateral testes, these increased enhancements caused by postoperative reactions have to be kept in mind.

Adult↗
PubMed1994

Central effect of rete testis fluid, inhibin 32K, and follicular fluid on plasma gonadotropin concentrations in sheep: inhibin is not the rete testis fluid protein able to suppress luteinizing hormone pulses.

We have previously shown that peripheral administration of rete testis fluid (RTF) proteins was able to suppress LH pulses through the suppression of LHRH pulses. This activity was named "LHRH Statin." The aims of the present work were to analyze LH inhibition after an intracerebroventricular injection of RTF and to determine whether inhibin is the factor responsible for this inhibition. Castrated rams (experiment 1) or ewes (experiment 2) received an intracerebroventricular injection of RTF, purified bovine inhibin 32K, bovine follicular fluid, or human serum albumin as control. Animals were bled every 15 min for 5 h before injection and for 7 h after injection. LH mean levels were significantly lowered (p < 0.01) only in the RFT-treated groups. FSH levels were not affected irrespective of group, source, or dose of inhibin. These experiments show first, that protein(s) present in ovine RTF can suppress LH secretion in sheep; second, that bovine follicular fluid or purified bovine inhibin 32K have no effect on LH secretion. Furthermore, the results suggest that centrally administered inhibin has no effect on FSH secretion under our experimental conditions. Together, these experiments clearly demonstrate that inhibin 32K does not exert any "LHRH statin" activity.

Animals↗
PubMed1989

Restoration of advanced spermatogenic cells in the experimentally regressed rat testis: quantitative relationship to testosterone concentration within the testis.

We examined the effect of exogenously administered testosterone (T) on the quantitative restoration of advanced spermatogenic cells in adult rat testes rendered azoospermic by treating rats with polydimethylsiloxane (PDS) implants of T and estradiol (E). Experimental rats received PDS-TE implants for an initial 8-week period; control rats received empty implants. By 8 weeks of PDS-TE treatment, rats became severely oligospermic, and the T concentration within the seminiferous tubule fluid (STF) was reduced approximately 80% (from 57.8 ng/ml in controls to 9.6 ng/ml). After the initial 8-week PDS-TE treatment, PDS-TE implants were removed from one group of rats; a second group of PDS-TE-implanted rats received an additional PDS-T implant of 24 cm. Eight weeks after the removal of PDS-TE implants or the implantation of additional T, testis weight and numbers of advanced spermatogenic cells were restored to those of control rats. The STF T concentration 8 weeks after the removal of PDS-TE implants also was restored to that in control rats. In contrast, the STF T concentration increased to only 40% of control values in the rats that received an additional T implant. Despite this 60% reduction in T concentration compared to the control value, advanced spermatogenic cell number was restored to a value indistinguishable from that of intact controls. These observations indicate that spermatogenesis can be quantitatively restored in PDS-TE-implanted rats with exogenously administered T, and moreover, that this restoration does not require the high T concentration found in the STF of intact control rats.

Animals↗
PubMed1978

Studies of the human testis. X. Properties of human chorionic gonadotropin receptor in adult testis and relation to intratesticular testosterone concentration.

Receptors for [125I]hCG were found in adult human testis. The specific binding of [125I]hCG to testicular receptor is temperature dependent and is a saturable process with respect to added receptor protein and hormone. Scatchard analysis revealed a dissociation constant of 5.0 X 10(-10) M, and 6.2 fmol binding site/mg protein. Intact unlabeled hCG effectively inhibits the specific binding of [125I]hCG to human testicular receptors. For inhibition of binding of [125I]hCG, the alpha subunit has 3.0% of the potency of intact hCG and the beta subunit has 0.4% of the potency of intact hCG. Specific binding is pH dependent, with an optimum at pH 7.4. Brief exposure to extremes of pH causes irreversible damage to the receptors. Incubation with protease and trypsin results in an almost complete loss of binding activity, while ribonuclease, deoxyribonuclease, phospholipase C, or neuraminidase treatment does not significantly alter hormone-binding activity. Binding activity was found to be positively correlated to the concentration of intratesticular testosterone.

Adult↗