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1.
J Therm Biol ; 100: 103064, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34503804

RESUMO

Ruminant testes are ~2-6 °C below body temperature; increased testicular temperature reduces sperm motility and morphology. Our objective was to serially monitor scrotal subcutaneous temperatures during testicular heat stress and relate those to sperm quality. Two experiments were conducted, with temperature sensors surgically implanted in scrotal subcutaneous tissues recording temperatures every 15 min and semen collected and evaluated weekly. After an initial control interval, testicular temperature was increased. In Experiment 1, in two Angus bulls, whole-scrotum insulation for 96 h increased scrotal subcutaneous temperatures by ~2.0-2.5 °C (P < 0.05). Total and progressive motility decreased (P < 0.05) and reached a nadir at Week 3 (~20 and 10%, respectively). Furthermore, morphologically normal sperm and acrosome integrity also decreased significantly, reaching nadirs at Weeks 3 (15%) and 4 (34%). In Experiment 2, 10 Dorset rams were allocated randomly into two equal groups and either: 1) exposed to 28 °C ambient temperature and 30-34% RH for 8 h/d for 4 d; or 2) subjected to scrotal neck insulation that was applied and removed at the same time as the start and completion, respectively, of heat exposures in the other rams. Scrotal subcutaneous temperatures (monitored in three rams per group) were increased in response to whole-body heating (~0.8 °C, P < 0.05), but not significantly changed by scrotal neck insulation. Decreases in sperm quality were generally similar between treatments, with the most profound changes evident 4 wk after heat stress, with ~10 percentage point reductions in both total and progressive motility and ~10 and 20 percentage point decreases in morphologically normal sperm in rams with whole-body heating versus scrotal neck insulation, respectively. In conclusion, scrotal subcutaneous temperature was significantly increased by scrotal insulation or whole-body heating, but not by scrotal neck insulation; however, all three heat-stress models decreased sperm motility and morphology in bulls and rams.


Assuntos
Bovinos/fisiologia , Transtornos de Estresse por Calor/prevenção & controle , Escroto/fisiologia , Ovinos/fisiologia , Temperatura Cutânea , Acrossomo/fisiologia , Animais , Regulação da Temperatura Corporal , Transtornos de Estresse por Calor/fisiopatologia , Transtornos de Estresse por Calor/veterinária , Masculino , Escroto/citologia , Análise do Sêmen/veterinária
2.
J Dairy Sci ; 102(6): 5623-5633, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30904295

RESUMO

The aim of the present study was to make a retrospective analysis of the relationship between climatic factors and sperm quality of frozen-thawed semen from bulls kept in temperate climates. Semen samples from 21 European dairy bulls from 2 countries were collected and cryopreserved in winter, spring, and summer. Sperm quality parameters such as kinematics, morphology, plasma membrane integrity, mitochondrial membrane potential, sperm chromatin structure assay, and reactive oxygen species were analyzed and correlated retrospectively with climate factors recorded by the local meteorological office. This study demonstrated that sperm quality parameters are more likely to be correlated with climate factors 1 or 2 mo before semen collection than in the month of semen collection. During the month of sperm collection, sperm kinematics, DNA fragmentation, and hydrogen peroxide production were the only sperm quality parameters related to climate factors, whereas 1 and 2 mo before sperm collection, normal morphology and additional sperm kinematics, in addition to DNA fragmentation and hydrogen peroxide production, were correlated with climate factors. In conclusion, dairy bull sperm quality is affected by climatic conditions, even in so-called temperate zones. The timing of heat stress during spermatogenesis determines which aspects of sperm quality are likely to be affected. Husbandry conditions for bulls used for semen collection should be adapted to allow the animals' physiological responses for temperature regulation within the scrotum to operate fully, to mitigate the effects of increased temperature and humidity. Extremes of temperature should be avoided.


Assuntos
Espermatozoides/química , Espermatozoides/citologia , Animais , Bovinos , Membrana Celular/química , Membrana Celular/metabolismo , Criopreservação , Fragmentação do DNA , Umidade , Masculino , Espécies Reativas de Oxigênio/metabolismo , Estudos Retrospectivos , Escroto/citologia , Escroto/metabolismo , Estações do Ano , Análise do Sêmen , Preservação do Sêmen , Motilidade dos Espermatozoides , Espermatogênese , Espermatozoides/metabolismo , Temperatura
3.
Hum Reprod ; 28(4): 877-85, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23411620

RESUMO

STUDY QUESTION: What are the effects of continuous sauna exposure on seminal parameters, sperm chromatin, sperm apoptosis and expression of genes involved in heat stress and hypoxia? SUMMARY ANSWER: Scrotal hyperthermia by exposure to sauna can induce a significant alteration of spermatogenesis. WHAT IS KNOWN ALREADY: Several authors have evidenced that high temperature has dramatic effects on spermatogenesis. STUDY DESIGN, SIZE AND DURATION: A longitudinal time-course study. Data from 10 subjects exposed to Finnish sauna were collected before sauna (T0), after 3 months of sauna sessions (T1) and after 3 (T2) and 6 months (T3) from the end of sauna exposure. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Ten normozoospermic volunteers underwent two sauna sessions per week for 3 months, at 80-90°C, each lasting 15 min. Sex hormones, sperm parameters, sperm chromatin structure, sperm apoptosis and expression of genes involved in heat stress and hypoxia were evaluated at the start, at the end of sauna exposure and after 3 and 6 months from sauna discontinuation. Student's t-test for paired data was used for statistical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: At the end of sauna exposure, we found a strong impairment of sperm count and motility (P < 0.001), while no significant change in sex hormones was present. Decreases in the percentage of sperm with normal histone-protamine substitution (78.7 ± 4.5 versus 69.0 ± 4.1), chromatin condensation (70.7 ± 4.7 versus 63.6 ± 3.3) and mitochondrial function (76.8 ± 4.9 versus 54.0 ± 6.1) were also evident at T1, and strong parallel up-regulation of genes involved in response to heat stress and hypoxia was found. All these effects were completely reversed at T3. LIMITATIONS AND REASONS FOR CAUTION: Absence of subjects with abnormal sperm parameters was the major limitation of this study. WIDER IMPLICATIONS OF THE FINDINGS: Our data demonstrated for the first time that in normozoospermic subjects, sauna exposure induces a significant but reversible impairment of spermatogenesis, including alteration of sperm parameters, mitochondrial function and sperm DNA packaging. The large use of Finnish sauna in Nordic countries and its growing use in other parts of the world make it important to consider the impact of this lifestyle choice on men's fertility. STUDY FUNDING/COMPETING INTEREST(S): No external funding was sought for this study and the authors have no conflict of interest to declare.


Assuntos
Resposta ao Choque Térmico/genética , Temperatura Alta , Espermatogênese/fisiologia , Banho a Vapor , Apoptose , Hipóxia Celular/genética , Hormônio Foliculoestimulante/sangue , Regulação da Expressão Gênica , Humanos , Inibinas/sangue , Estudos Longitudinais , Hormônio Luteinizante/sangue , Masculino , Escroto/citologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Testosterona/sangue
4.
J Med Food ; 14(9): 944-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21663474

RESUMO

Rosmarinus officinalis L. (Lamiaceae), popularly known as rosemary, is used for food flavoring and in folk medicine as an antispasmodic, analgesic, antirheumatic, diuretic, and antiepileptic agent. Few studies have shown the anti-inflammatory effects of rosemary essential oil (REO). This study evaluated the effects of REO on leukocyte migration through in vivo leukocyte migration and in vitro chemotaxis assay. REO was analyzed by using gas chromatography-mass spectometry, and the main components identified were camphor (27.59%), 1,8-cineole (15.74%), α-pinene (16.58%), and ß-myrcene (10.02%). In rats, administration of REO reduced the number of leukocytes that rolled, adhered, and migrated to the scrotal chamber after carrageenan injection. All doses of REO tested significantly inhibited leukocyte chemotaxis induced by casein. The effects of REO on leukocyte migration highlight an important mechanism of the anti-inflammatory action of rosemary.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Inibição de Migração Celular , Quimiotaxia de Leucócito/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Carragenina/toxicidade , Ensaios de Migração de Leucócitos , Relação Dose-Resposta a Droga , Endotélio/citologia , Endotélio/efeitos dos fármacos , Endotélio/imunologia , Cromatografia Gasosa-Espectrometria de Massas , Teste de Inibição de Aderência Leucocítica , Leucócitos/citologia , Leucócitos/imunologia , Espectroscopia de Ressonância Magnética , Masculino , Medicina Tradicional , Monoterpenos/análise , Monoterpenos/química , Monoterpenos/farmacologia , Óleos Voláteis/administração & dosagem , Óleos Voláteis/química , Folhas de Planta/química , Ratos , Ratos Wistar , Rosmarinus/química , Escroto/citologia , Escroto/efeitos dos fármacos , Escroto/imunologia
5.
Anim Reprod Sci ; 124(1-2): 138-44, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21377298

RESUMO

Levels of testosterone and insulin-like peptide 3 (INSL3) secretions in response to different doses of human chorionic gonadotropin (hCG) in cultured interstitial cells were compared between retained and scrotal testes in dogs. Retained (n=10) and scrotal (n=9) testes were obtained from small-breed dogs. The testicular tissues were dispersed in Dulbecco's Modified Eagle Medium with Ham's nutrient mixture containing 2000 PU/ml dispase II and 10% fetal bovine serum. The cells were plated with differing concentrations (0-10 IU/ml) of hCG for 18 h in multiwell-plates. Testosterone and INSL3 in the same spent medium were measured by enzyme-immunoassays (EIA). A new EIA with a reliable detection range of 0.025-5 ng/ml was developed in order to measure canine INSL3 in culture medium. Dose-dependent stimulation of testosterone by hCG was observed in the cells of both retained and scrotal testes. The incremental rate of testosterone secretion was significantly lower at 0.1, 1 and 10 IU/ml hCG in the cells of retained testes than in scrotal testes, however. INSL3 secretion was significantly stimulated at 10 IU/ml hCG relative to unstimulated controls comprising cells of scrotal testes; no such stimulation was observed in the cells of retained testes. At 10 IU/ml hCG, the incremental rate of INSL3 was significantly lower in the cells of retained testes than scrotal testes. These results suggest that LH-induced secretory testosterone and INSL3 responses are lower in the interstitial cells of retained testes than of scrotal testes. Furthermore, the high concentrations of LH may acutely stimulate INSL3 release in scrotal testes of dogs, but not in retained testes.


Assuntos
Gonadotropina Coriônica/farmacologia , Insulina/biossíntese , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Testosterona/biossíntese , Animais , Células Cultivadas , Criptorquidismo/veterinária , Doenças do Cão , Cães , Masculino , Proteínas , Escroto/citologia , Testículo/citologia
7.
Vet J ; 163(1): 68-76, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11749138

RESUMO

The present study describes the glycosidic content of the interstitial tissue in testes from healthy boars and from unilateral and bilateral abdominal cryptorchid boars using lectin histochemistry. The Leydig cells of healthy boars contained glycans with fucosyl, mannosyl, glucosyl, neuraminic acid and galactosyl residues, which have structural and transport functions, and participate in androgen synthesis and in cell regulation. Unilateral cryptorchidism induced high glucosyl and low galactosyl content in the Leydig cells of scrotal testes, resulting in impaired androgen production. In abdominal testes, the Leydig cells exhibited increased amounts of glucosyl and reduced amounts of galactosyl and neuraminic acid residues, resulting in defective cell regulation and lack of androgen synthesis. In healthy boars, the extracellular glycans contained fucosyl, galactosyl, glucosyl and neuraminic acid residues, which confer viscoelasticity on the interstitial tissue and participate in substrate transport, hormone binding and cell-cell interaction. Unilateral cryptorchidism did not induce anomalies in extracellular glycans in scrotal testes, but unilateral and bilateral cryptorchidism resulted in an increased content of fucosyl and galactosyl, and a decreased content of glucosyl and neuraminic acid residues in abdominal testes, leading to reduced viscoelasticity and defective substrate transport across the extracellular matrix.


Assuntos
Criptorquidismo/veterinária , Lectinas/metabolismo , Escroto/citologia , Doenças dos Suínos/metabolismo , Testículo/citologia , Animais , Criptorquidismo/patologia , Fibroblastos , Histocitoquímica/veterinária , Células Intersticiais do Testículo , Masculino , Suínos , Doenças dos Suínos/patologia , Testículo/patologia
8.
J Androl ; 22(5): 863-77, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11545301

RESUMO

Scrotal contents of 2 rams were insulated for 96 hours and the fraction (as a percentage) of clusterin-positive cells (CPCs) and its relationship to semen quality was investigated. Semen collection was started 18 days before insulation and was terminated on day 78 and day 63 after insulation in animals 1 and 2, respectively. Sperm clusterin was localized by immunostaining with anti-bovine clusterin antibody (anti-bCAb) and fluorescein isothiocyanate-conjugated immunoglobulin G. Scrotal insulation led to deterioration of semen quality and increased the percentage of CPCs in both rams. Two types of sperm reactivity were observed: an extensive, intensive staining pattern (ESP); and a localized, less-intensive staining pattern (LSP). The percentage of ESP-CPCs began to increase from day 6 and reached 88.8% and 100% on day 15 after insulation in animals 1 and 2, respectively. The increase in CPCs coincided with the presence of a high percentage of teratoid forms (88.3%) in semen from animal 1, and detached heads (81.4%) in semen from animal 2. After normal semen production was restored on day 60 in animal 1, the percentages of ESP-CPCs and LSP-CPCs returned to preinsulation rates, whereas only the ESP-CPCs returned to normal in animal 2. A negative relationship was observed between ESP-CPCs and total sperm/ejaculate (r = -.62), motility (r = -.78), viability (r = -.68), and filtration rate (r = -.71) in semen from animal 1. Conversely, a positive relationship was seen between ESP-CPCs and total abnormal spermatozoa (r = .82). Similar results were obtained in semen from animal 2. CPCs were nearly completely absent in glass wool-Sephadex (GWS)-filtered semen, suggesting a role for clusterin in the process of trapping abnormal spermatozoa in the GWS filters. We conclude that aberrant spermatogenesis induced by scrotal insulation increases the percentage of CPCs in ram semen. We suggest that the percentage of CPCs in ram semen could be a useful marker in poor-quality ejaculates.


Assuntos
Glicoproteínas/metabolismo , Chaperonas Moleculares/metabolismo , Escroto/citologia , Sêmen/citologia , Espermatozoides/metabolismo , Animais , Clusterina , Masculino , Ovinos , Motilidade dos Espermatozoides , Espermatozoides/fisiologia
9.
Tissue Cell ; 33(1): 8-24, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11292175

RESUMO

The interstitial tissue of the testes from healthy boars, and unilateral and bilateral abdominal cryptorchid boars was examined by light and transmission electron microscopy. The left and right testes of healthy boars, and the left (scrotal) testis of unilateral cryptorchid boars had abundant mature Leydig cells, few fibroblasts and mast cells, scarce and small blood vessels, and little lymphatic areas. The right (abdominal) testis of unilateral cryptorchid boars contained abundant Leydig cells, fibroblasts and erythrocytes, scarce mast cells, and frequent blood vessels; Leydig cells exhibited either a mature but degenerative appearance or an immature appearance, and fibroblasts displayed immaturity signs. The interstitial tissue of the left (abdominal) testes of bilateral cryptorchid boars had small blood vessels surrounded by erythrocytes, lymphocytes, and few plasma cells, and abundant mature and immature Leydig cells, immature fibroblasts, and mast cells. Mature Leydig cells showed mid or advanced degeneration, and immature Leydig cells displayed either non-degenerative or degenerative patterns. The right (abdominal) testes of bilateral cryptorchid boars contained scarce immature Leydig cells in advanced degeneration, large fibrous and adipose areas, and blood vessels. These results indicated that unilateral abdominal cryptorchidism affect neither the structural nor the cytologic features of the interstitial tissue in scrotal testes. Unilateral and bilateral cryptorchidism induced abnormal differentiation of Leydig cells and fibroblasts leading to decreased steroid production and increased collagenization in abdominal testes.


Assuntos
Criptorquidismo/patologia , Escroto/anatomia & histologia , Escroto/patologia , Suínos/anatomia & histologia , Testículo/citologia , Testículo/patologia , Animais , Contagem de Células , Fibroblastos/patologia , Fibroblastos/ultraestrutura , Células Intersticiais do Testículo/patologia , Células Intersticiais do Testículo/ultraestrutura , Masculino , Mastócitos/patologia , Mastócitos/ultraestrutura , Microscopia Eletrônica , Tamanho do Órgão , Escroto/citologia , Maturidade Sexual
10.
Teratology ; 63(1): 42-51, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11169554

RESUMO

BACKGROUND: Few data exist about the features of testicular microvasculature under normal and pathologic conditions. METHODS: The morphology and lectin affinity of testicular capillaries were examined in healthy boars and in unilateral and bilateral abdominal cryptorchid boars. RESULTS: The capillaries of scrotal testes contained a) the endothelial layer formed by two cells, b) the basal lamina constituted by collagen fibers and glycoconjugates with fucosyl, galactosyl, glucosyl, and neuraminic acid residues, and c) the pericyte layer formed by a single cell. These components participated in substrate exchange between blood and testicular tissue. The abdominal testes showed increased numbers of capillaries, which could exhibit a mature appearance, but also angiogenic or degenerative patterns. Angiogenesis was manifested in interstitial capillaries and was characterized by a) proliferation of endothelial cells, b) decreased thickness and decreased content of collagen fibers and glycoconjugates in the basal lamina, and c) lack of pericytes. Degenerative capillaries lay in association with seminiferous tubules and showed a) pyknotic endothelial cells; b) thickening, collagenization, and altered glycoconjugate content in the basal lamina; and c) increased development of pericytes. The angiogenesis of interstitial capillaries resulted in high vascular permeability, and the degeneration of intertubular capillaries led to defective substrate exchange between blood and seminiferous tubules. CONCLUSIONS: Unilateral abdominal cryptorchidism did not alter the morphology and function of capillaries in the scrotal testis. Unilateral and bilateral abdominal cryptorchidism resulted in increased numbers and abnormal morphology and function of capillaries in abdominal testes. The proliferation of interstitial capillaries correlated with the immaturity of Leydig cells, and the degeneration of intertubular capillaries correlated with the thickening of the lamina propria.


Assuntos
Capilares/patologia , Criptorquidismo/veterinária , Glicoconjugados/análise , Doenças dos Suínos/patologia , Testículo/irrigação sanguínea , Animais , Capilares/citologia , Capilares/ultraestrutura , Criptorquidismo/patologia , Lectinas , Masculino , Valores de Referência , Escroto/irrigação sanguínea , Escroto/citologia , Escroto/patologia , Suínos , Testículo/citologia , Testículo/patologia
11.
Biol Reprod ; 60(3): 615-20, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10026107

RESUMO

A variety of testicular insults can induce changes in the structure of spermatozoal chromatin, resulting in spermatozoal DNA that is more susceptible to acid-induced denaturation. The degree of change in the DNA can be measured using the sperm chromatin structure assay (SCSA). The SCSA measures the relative amounts of single- and double-stranded DNA after staining with the metachromatic dye, acridine orange. Here we used a stallion model (n = 4) to study the effects of scrotal heat stress on spermatozoal DNA. This model was created by insulating stallion testes for 48 h and collecting sperm daily thereafter for 60 days. Changes in the SCSA were then correlated with protamine disulfide content and protamine types and levels. Results of the SCSA indicated that the susceptibility of spermatozoal DNA to denaturation was dependent on the spermatogenic cell stage that the ejaculated sperm was in at the time of the heat stress. Spermatozoa with altered DNA had a decrease in the extent of disulfide bonding that was associated with an increase in the susceptibility of DNA to denaturation. However, there were no detectable changes in either the protamine type or level. Thus, in this model, decreased disulfide bonding is associated with an increased susceptibility of spermatozoal DNA to denaturation in the absence of protamine changes.


Assuntos
Cromatina/ultraestrutura , Dissulfetos/metabolismo , Cavalos , Temperatura Alta , Escroto/citologia , Espermatozoides/ultraestrutura , Animais , Cromatina/química , DNA/análise , DNA/química , Feminino , Masculino , Desnaturação de Ácido Nucleico , Protaminas/metabolismo
12.
Mod Pathol ; 11(3): 282-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9521476

RESUMO

We discuss here three cases of scrotal leiomyoma with bizarre nuclei. The patients, ranging in age from 44 to 58 years, presented with painless scrotal masses that were clinically diagnosed as cysts. Clinical follow-up, available for two of the patients, revealed no evidence of local recurrence or distant metastasis 5 years after resection. The tumors were well circumscribed and ranged from 2 to 3 cm in maximal diameter. They were characterized by interlacing fascicles of spindle-shaped cells with pleomorphic nuclei. Nuclei were large and multilobulated with hyperchromatic chromatin and macronucleoli. Multinucleated tumor cells were infrequent. Intranuclear invagination of eosinophilic globules of cytoplasm produced pseudonucleoli. There was no mitotic activity. Immunohistochemically, the tumor cells expressed vimentin, desmin, smooth muscle actin, and muscle-specific actin, but not cytokeratin, neurofilament, or glial fibrillary acidic protein. In contrast to scrotal leiomyosarcomas, scrotal leiomyomas with bizarre nuclei are not hypercellular, and they lack mitotic activity.


Assuntos
Neoplasias dos Genitais Masculinos/patologia , Leiomioma/patologia , Escroto/patologia , Actinas/análise , Actinas/imunologia , Adulto , Núcleo Celular/patologia , Desmina/análise , Desmina/imunologia , Neoplasias dos Genitais Masculinos/química , Células Gigantes/patologia , Humanos , Imuno-Histoquímica , Leiomioma/química , Masculino , Pessoa de Meia-Idade , Escroto/citologia , Escroto/ultraestrutura , Vimentina/análise , Vimentina/imunologia
13.
Mol Cell Endocrinol ; 98(1): 55-9, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8143914

RESUMO

Regulation of steroid 5 alpha-reductase (5 alpha R) activity and dihydrotestosterone (DHT) formation is central to prostate and sexual skin (hair) growth and cell function. Transforming growth factor-beta 1 (TGF-beta 1) is a ubiquitous peptide present in skin and scrotal tissue and its receptor is universally expressed. We have explored the role of TGF-beta 1 and -beta 2 on androgen formation in skin. Rat or human sexual skin fibroblasts were grown in primary cultures (passage 3-7). 5 alpha-Reductase activity was measured by the %-conversion of tracer 3H-testosterone to dihydrotestosterone over a 4 h period. Incubation of scrotal fibroblasts (2 x 10(5) cells) in serum and growth factor free media with androgen, such as DHT for two days significantly stimulates 5 alpha R in these cells (1.6-fold, p < 0.05 vs control). TGF-beta 1 alone at picomolar concentrations (2 x 10(-11) M to 2 x 10(-10) M) was a potent inducer of 5 alpha R activity in both rat (1.8-fold and 2.8-fold, respectively, p < 0.001 vs control at both doses) and human cells (TGF-beta 1 2 x 10(-10) M 3.3-fold, p < 0.001 vs control). Combined exposure of these fibroblasts to TGF-beta 1 (2 x 10(-10) M) and androgen (10(-7) M) further potentiated 5 alpha R activity (rat cells 6.5-fold, human cells 6.4-fold, p < 0.001 vs DHT or TGF-beta 1 alone).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/biossíntese , Fator de Crescimento Epidérmico/farmacologia , Fibroblastos/efeitos dos fármacos , Escroto/enzimologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Células Cultivadas , Meios de Cultura Livres de Soro , Di-Hidrotestosterona/metabolismo , Di-Hidrotestosterona/farmacologia , Sinergismo Farmacológico , Fibroblastos/enzimologia , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Escroto/citologia , Testosterona/metabolismo , Testosterona/farmacologia
16.
Anat Rec ; 193(1): 43-53, 1979 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-760595

RESUMO

The effects of UVL-B and/or testosterone replacemnt therapy are compared in normal and castrated rats in order to determine whether testosterone is required for UVL-B (290-315 nm) stimulation of melanogenesis in the testosterone-dependent epidermal melanocyte system of the scrotal skin of black Long Evans rats. Testosterone is not a prerequisite for UVL-B stimulation of melanocytes as in both castrates and normal animals the melanocytes respond to UVL-B by increases in size, length and number of dendrites (dendriticness), and tyrosinase activity (intensity of Dopa reaction). Addition of testosterone to castrates does enhance the effects of UVL-B. However, UVL-B with or without testosterone cannot maintain normal melanogenesis in rats irradiated immediately after castration nor can it restore normal melanogenesis following long term castration. Bth the amount of UVL nergy/exposure and the number of exposures are important variables in stimulation of the epidermal melanocytes. Administration of a dose of UVL-B to castrates in a single exposure is ineffective, while the same overall dose spread over several exposures increases the size and dendriticness of melanocytes. Testosterone and UVL-B act synergistically in affecting melanogenesis although neither singly nor in combination are they able to fully restore normal melanogenesis.


Assuntos
Melanócitos/citologia , Escroto/citologia , Testosterona/farmacologia , Raios Ultravioleta , Animais , Castração , Contagem de Células , Masculino , Melanócitos/efeitos dos fármacos , Melanócitos/efeitos da radiação , Ratos , Pele/citologia
17.
Endocrinology ; 103(4): 1499-505, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-744162

RESUMO

The uptake of [1,2,4,5,6,7-3H]dihydrotestosterone into whole cells and nuclei has been assessed in fibroblasts grown from genital skin of 10 controls and 9 subjects with hereditary male pseudohermaphroditism due to androgen resistance. The cells were exposed to hypotonic buffer and ruptured by passage through a 25-gauge needle, and the nuclei were purified by sedimentation through 2.1 M sucrose. Uptake of the hormone into nuclei reached an apparent plateau in 45 min, was saturable at 1 nM dihydrotestosterone, and was not detectable in the presence of excess nonradioactive hormones. Over a wide range of uptake by intact cells from control subjects and from subjects with androgen resistance due to 5alpha-reductase deficiency or receptor deficiency, nuclear uptake averaged about half of the total cell uptake. Furthermore, in cells from two unrelated 46,XY phenotypic females with androgen resistance but normal 5alpha-reductase activity and normal whole cell dihydrotestosterone binding, uptake into the nucleus was also normal. In these subjects, the defect in androgen action must be at some terminal phase of androgen action.


Assuntos
Di-Hidrotestosterona/metabolismo , Fibroblastos/metabolismo , Adolescente , Androgênios/farmacologia , Núcleo Celular/metabolismo , Células Cultivadas , Transtornos do Desenvolvimento Sexual/metabolismo , Resistência a Medicamentos , Humanos , Masculino , Escroto/citologia
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