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1.
Horm Metab Res ; 46(5): 305-12, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24446158

RESUMO

Thyroid-stimulating hormone exerts both antiresorptive and anabolic effects on bone remodeling in aged ovariectomized rats and thyroid stimulating hormone-receptor null mice, supported by clinical results demonstrating that low thyroid-stimulating hormone level is associated with increased bone loss. To further explore the effect of thyroid-stimulating hormone on bone metabolism we introduced here a rat model with removed thyroid and parathyroid glands to obtain low serum concentrations of thyroid and parathyroid hormone, calcitonin and 1,25(OH)2D3. Surgery resulted in hypocalcemia, low parathyroid and thyroid hormone, 1,25(OH)2D3, C-telopeptide, and osteocalcin serum level. Intermittent administration of thyroid-stimulating hormone resulted in a further decrease of serum calcium and decreased level of serum C-telopeptide due to the suppression of bone resorption, while in the same animals osteocalcin in serum was higher indicating an increased bone formation rate. A combination of thyroid-stimulating hormone and 1,25(OH)2D3 significantly increased the serum Ca2+, C-telopeptide and serum osteocalcin values. MicroCT analyses of the distal femur and proximal tibia showed that rats treated with 1,25(OH)2D3 alone or in a combination with thyroid-stimulating hormone had an increased trabecular bone volume, and enhanced trabecular bone quality. Biomechanical testing of the trabecular bone showed an increased maximal load for 105% and 235%, respectively, in rats treated with 1,25(OH)2D3 alone, or in a combination with thyroid-stimulating hormone. We suggest that thyroid-stimulating hormone independently of calciotropic hormones suppressed bone resorption and stimulated bone formation, while in combination with 1,25(OH)2D3 acted synergistically on bone formation resulting in an increased bone volume.


Assuntos
Reabsorção Óssea , Osso e Ossos/metabolismo , Calcitonina/metabolismo , Calcitriol/metabolismo , Hormônio Paratireóideo/metabolismo , Tireotropina/metabolismo , Animais , Densidade Óssea , Desenvolvimento Ósseo , Osso e Ossos/química , Cálcio/sangue , Colágeno Tipo I/sangue , Masculino , Osteocalcina/sangue , Peptídeos/sangue , Ratos , Ratos Sprague-Dawley
2.
Reprod Toxicol ; 113: 96-102, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35961531

RESUMO

Male infertility, a condition that has during the last decade raised significant concern, is a diagnostically demanding and socially sensitive topic. The number of unsolved issues on infertility etiology, especially potential environmental causes, in couples demonstrates the need for further investigations into infertility biomarkers. Semen parameters are often insufficient for reliable profiling of male infertility. Thus, this study aims to evaluate for the first time seminal plasma N-glycosylation as a biomarker of environmental exposure in semen samples from 82 normozoospermic men and 84 men with abnormal semen parameters and compare it with genome damage measured by DNA fragmentation. We obtained information about chronic exposure to environmental factors from the self-reported questionnaire, and determined sperm DNA fragmentation by sperm chromatin dispersion, while N-glycans were characterized with liquid chromatography-mass spectrometry (LC-MS). Based on previously published results, ten N-glycans were selected. Results show that the selected seminal plasma N-glycans were significantly associated with smoking, exposure to pesticides, air pollution, agents emitted during photocopying, alcohol consumption, and obesity. Some N-glycans showed a simultaneous association with DNA fragmentation, semen parameters, and environmental stressors. These subgroups of N-glycans are new potential candidates for biomonitoring of exposure to different environmental factors in men with semen abnormalities.


Assuntos
Infertilidade Masculina , Praguicidas , Biomarcadores/análise , Cromatina , Fragmentação do DNA , Exposição Ambiental/efeitos adversos , Humanos , Infertilidade Masculina/genética , Masculino , Praguicidas/análise , Polissacarídeos/análise , Sêmen/química , Análise do Sêmen , Motilidade dos Espermatozoides , Espermatozoides
3.
Mutat Res ; 658(1-2): 111-123, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18155954

RESUMO

During the last decade, our knowledge of the mechanisms by which children respond to exposures to physical and chemical agents present in the environment, has significantly increased. Results of recent projects and programmes focused on children's health underline a specific vulnerability of children to environmental genotoxicants. Environmental research on children predominantly investigates the health effects of air pollution while effects from radiation exposure deserve more attention. The main sources of knowledge on genome damage of children exposed to radiation are studies performed after the Chernobyl nuclear plant accident in 1986. The present review presents and discusses data collected from papers analyzing genome damage in children environmentally exposed to ionizing radiation. Overall, the evidence from the studies conducted following the Chernobyl accident, nuclear tests, environmental radiation pollution and indoor accidental contamination reveals consistently increased chromosome aberration and micronuclei frequency in exposed than in referent children. Future research in this area should be focused on studies providing information on: (a) effects on children caused by low doses of radiation; (b) effects on children from combined exposure to low doses of radiation and chemical agents from food, water and air; and (c) specific effects from exposure during early childhood (radioisotopes from water, radon in homes). Special consideration should also be given to a possible impact of a radiochemical environment to the development of an adaptive response for genomic damage. Interactive databases should be developed to provide integration of cytogenetic data, childhood cancer registry data and information on environmental contamination. The overall aim is to introduce timely and efficient preventive measures, by means of a better knowledge of the early and delayed health effects in children resulting from radiation exposure.


Assuntos
Aberrações Cromossômicas/efeitos da radiação , Dano ao DNA , Exposição Ambiental/efeitos adversos , Radiação Ionizante , Acidente Nuclear de Chernobyl , Criança , Relação Dose-Resposta à Radiação , Humanos , Liberação Nociva de Radioativos
4.
Appl Spectrosc ; 61(3): 309-13, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17389071

RESUMO

Fourier transform infrared (FT-IR) spectra of human spermatozoa and seminal plasma were recorded and analyzed. The procedure that was established for sample preparation enabled acquisition of reproducible spectra. The parameter I(1087)/I(966) for controlling spectra reproducibility was defined. The assignment of bands was carried out using an empirical approach and the origin of the "sperm specific doublet", the bands at 968 cm(-1) and 981 cm(-1), was determined. The principal component regression (PCR) algorithm was used to define the specific spectral regions correlating to characteristics of spermatozoa, such as concentration, straight-line velocity (VSL), and beat cross frequency (BCF). Then, simple spectral parameters, such as band intensities and band ratios, were tested to determine which one best correlates to characteristics of spermatozoa. The region of the amide I band, between 1700 cm(-1) and 1590 cm(-1), was defined as a specific spectral region that correlates to the concentration of spermatozoa. The parameter that gave the linear dependence to the concentration of spermatozoa was the intensity of the amide I band. For VSL, the bands between 1119 cm(-1) and 943 cm(-1) were defined as the specific spectral region. The relative amount of nucleic acids with respect to proteins showed linear dependence on the straight-line velocity of spermatozoa. BCF showed the best correlation to the bands between 3678 cm(-1) and 2749 cm(-1), which largely represent lipids and proteins. These results suggest that FT-IR spectroscopy can serve as an adjunct to conventional histopathology studies.


Assuntos
Algoritmos , Sêmen/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espermatozoides/química , Humanos , Masculino
5.
Endocrinology ; 145(3): 1419-26, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14630712

RESUMO

Mammalian lanosterol 14 alpha-demethylase (CYP51) is a microsomal cytochrome P450 that demethylates lanosterol to FF-MAS, an oocyte meiosis-activating sterol and late intermediate of cholesterol biosynthesis. Herein we report CYP51 unequivocally localized to acrosomal membranes of male germ cells in mouse, bull, and ram, in which it synthesizes FF-MAS in the presence of the acrosomal form of nicotinamide adenine dinucleotide phosphate reduced-P450 reductase. In the mouse, CYP51 (53 kDa) resides in endoplasmic reticulum (ER) and Golgi during all phases of acrosome development, indicating an intracellular transport from ERs through the Golgi to the acrosome. CYP51 (50 kDa) also resides on acrosomal membranes of bull- and ram-ejaculated sperm. In mouse liver, a 53-kDa CYP51 is no longer detected in trans Golgi, suggesting retrieval back to the ER and no further transport to other organelles. Glycosylated high-molecular-mass CYP51-immunoreactive proteins in acrosomal membranes of bull and ram and Golgi-enriched fractions of mouse liver indicate that mammalian CYP51s are subjected to posttranslational modifications in the Golgi. In conclusion, CYP51 is the first cytochrome P450 enzyme to be detected on acrosomal membranes. It exhibits a unique, cell-type-specific intracellular transport that is in agreement with its cell-type-specific physiological role: production of cholesterol in the liver and sterols with signaling properties in sperm. Demethylation of lanosterol to FF-MAS by the acrosomal lanosterol 14 alpha-demethylase enzyme complex demonstrates for the first time the ability of ejaculate sperm to synthesize meiosis-activating sterols.


Assuntos
Acrossomo/enzimologia , Sistema Enzimático do Citocromo P-450/metabolismo , Complexo de Golgi/metabolismo , Meiose/fisiologia , Oxirredutases/metabolismo , Animais , Bovinos , Fracionamento Celular , Ejaculação , Fígado/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos CBA , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Ovinos , Espermátides/enzimologia , Espermatozoides/enzimologia , Esterol 14-Desmetilase , Esteróis/biossíntese , Testículo/citologia , Testículo/enzimologia
6.
Neurology ; 59(12): 1994-7, 2002 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-12499502

RESUMO

Graft-vs-host disease (GVHD) is a potentially treatable cause of progressive neurologic decline after bone marrow transplantation (BMT). The authors present histologic confirmation of CNS granulomatous angiitis in a child with chronic GVHD after BMT. Since cranial MRI showed only nonspecific findings, CNS vasculitis associated with GVHD after BMT may be underdiagnosed.


Assuntos
Transtornos Cerebrovasculares/etiologia , Doença Enxerto-Hospedeiro/complicações , Vasculite/etiologia , Adolescente , Corticosteroides/uso terapêutico , Transplante de Medula Óssea/efeitos adversos , Encéfalo/patologia , Transtornos Cerebrovasculares/tratamento farmacológico , Transtornos Cerebrovasculares/patologia , Feminino , Doença Enxerto-Hospedeiro/patologia , Humanos , Leucemia Mieloide Aguda/cirurgia , Vasculite/tratamento farmacológico , Vasculite/patologia
7.
Transplantation ; 53(1): 80-6, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1531095

RESUMO

T10B9.1A-31, a nonmitogenic immunoglobulin Mk monoclonal antibody that detects an epitope on the alpha/beta chains of the T cell antigen receptor (TCR alpha/beta), or OKT3, an anti-CD3 mAb, was employed in a randomized double-blind phase II clinical trial to treat biopsy-proven acute cellular renal allograft rejection. Two of the 40 patients initially selected for the protocol were considered to be nonevaluable. Analysis of the remaining 38 patients receiving both living related and cadaveric donor allografts revealed a patient survival of 100% and a graft survival of 97%. Primary rejection reversal was achieved in 18/19 (95%) patients treated with T10B9.1A-31 and in 20/21 (95%) of patients receiving OKT3. The two patients who did not respond to the first mAb responded to the crossover mAb. Rerejection occurred in 3/18 (17%) of patients treated with T10B9.1A-31 and in 3/20 (15%) treated with OKT3. The mean day of rejection reversal was 1.9 +/- 0.7 with T10B9.1A-31 and 3.37 +/- 1.21 with OKT3 treatment. The rise in mean serum creatinine after mAb administration and the mean creatinine on days 1 through 6 were significantly less in patients treated with T10B9.1A-31. Biopsy specimens analyzed for rejection revealed no significant difference between the T10B9.1A-31 and OKT3 cohorts. The mean serum creatinines at 30, 60, 180, and 360 days posttransplantation were the same for both groups. Significantly fewer febrile, respiratory, and untoward effects followed the first dose (day 0) and fewer febrile, gastrointestinal, and neurological side effects occurred with subsequent doses (days 1-9) in patients treated with T10B9.1A-31. Infectious complications occurred in 3/13 patients treated only with T10B9.1A-31, in 9/17 OKT3-treated patients, and in 4/8 patients treated with both mAb. Analysis of human antimouse antibody (HAMA) revealed that the development of HAMA with T10B9.1A-31 was similar to that of OKT3.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Rejeição de Enxerto , Transplante de Rim , Muromonab-CD3/uso terapêutico , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Adulto , Animais , Anticorpos Anti-Idiotípicos/análise , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Infecções Bacterianas/etiologia , Biópsia , Método Duplo-Cego , Feminino , Sobrevivência de Enxerto , Humanos , Interferon gama/sangue , Rim/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Linfócitos T/imunologia , Transplante Homólogo , Fator de Necrose Tumoral alfa/análise
8.
Transplantation ; 56(1): 113-20, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8333033

RESUMO

Clinical acute graft-versus-host disease (aGVHD) was correlated with alterations in PBL phenotype and skin immunohistology in 52 patients transplanted with HLA-identical bone marrow. Concurrent with the emergence of aGVHD, there was a profound decrease in absolute number of CD3- T cells and an increase in CD3-CD16+, CD56+ (a subset of which coexpress CD8+ "dim") NK cells in the PBL. CD4+ T and CD20+ B lymphocytes failed to recover within 90 days in the patients with grades II-IV aGVHD. Ex vivo partial T cell depletion, in itself, did not significantly impair T cell recovery as compared to that in non-T-depleted recipients unless aGVHD occurred. Although leukocytic cellular infiltration in the skin was generally sparse, CD16+ NK lymphocytes were significantly increased in grades II-IV aGVHD. By contrast, there was no significant increase in CD3+, CD4+, or CD8+ lymphocytes in these lesions as compared to skin biopsies obtained from BMT patients without aGVHD or from normal skin. Taken together, these findings suggest that NK cells may be important in the pathogenesis of human aGVHD.


Assuntos
Transplante de Medula Óssea/imunologia , Doença Enxerto-Hospedeiro/imunologia , Células Matadoras Naturais/imunologia , Doença Aguda , Adolescente , Adulto , Antígenos CD/análise , Subpopulações de Linfócitos B/imunologia , Complexo CD3/análise , Criança , Citometria de Fluxo , Doença Enxerto-Hospedeiro/prevenção & controle , Teste de Histocompatibilidade , Humanos , Imunofenotipagem , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Receptores de IgG/análise , Pele/imunologia , Pele/patologia , Subpopulações de Linfócitos T/imunologia
9.
Virchows Arch ; 427(5): 497-502, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8624579

RESUMO

The intermediate filament of mature human Sertoli cells is vimentin. A co-expression of vimentin together with cytokeratin has been demonstrated in Sertoli cells during embryonal development and under pathologic conditions in adult testes. We analysed the presence of vimentin, cytokeratin, and desmin in Sertoli cells of fetal testes (n=20), in seminiferous tubules of cryptorchid testes (n=10) and adjacent to testicular germ cell tumours (n=47) using specific monoclonal antibodies and single and double-labelling immunohistochemistry. During embryonal development prominent cytokeratin expression disappears after the 20th week of gestation. Interestingly, we also found desmin in immature intratubular Sertoli cells between weeks 11 and 14. In adult cryptorchid testes and in peritumour tubules, desmin was also prominently present in Sertoli cells in the vast majority of the cases investigated, as well as vimentin and cytokeratin co-expression. This first description of desmin immunoreactivity may shed some light on the ontogeny of human Sertoli cells and demonstrates that this cell type is able to express three types of intermediate filaments in a complex manner.


Assuntos
Criptorquidismo/metabolismo , Feto/química , Proteínas de Filamentos Intermediários/metabolismo , Células de Sertoli/metabolismo , Neoplasias Testiculares/metabolismo , Testículo/química , Adulto , Criptorquidismo/patologia , Desmina/metabolismo , Feminino , Humanos , Recém-Nascido , Queratinas/metabolismo , Masculino , Gravidez , Células de Sertoli/patologia , Neoplasias Testiculares/patologia , Testículo/embriologia , Testículo/patologia , Vimentina/metabolismo
10.
Anat Embryol (Berl) ; 193(2): 181-90, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8742059

RESUMO

Testicular peritubular cells are located in the lamina propria of seminiferous tubules. These cells, significantly contributing to the basal membrane of seminiferous epithelium, have been studied in a number of species. However, there is a lack of data on the development of the lamina propria in the human testis. The aim of our survey was to investigate the characteristics of the lamina propria and, in particular, peritubular cells in the fetal human testes by immunohistological and stereological methods. Therefore, testes (14-39 weeks of gestation, n = 45) were dissected and fixed in a 4% buffered paraformaldehyde solution. Several pieces of each testis were embedded in paraffin and processed for immunohistochemical and stereological analysis. All investigated testes have shown sex cords in the process of development and differentiation. Morphologically, peritubular cells in the lamina propria can be divided into two types: fibroblast-like (FL) and myoid-like (ML) type (cells which much resemble mature myoid cells). By immunohistochemistry, both FL and ML cells are found to be strongly positive for the intermediate filament desmin, but negative for alpha-smooth actin. While FL cells intensively express Ki-67 demonstrating proliferative activity, ML cells are found to be negative. The basement membrane of sex cords as well as the blood vessels of the interstitium show strong positivity to collagen IV and laminin. Concerning the correlation between the appearance of the investigated antigens with the gestational age, all antigens have been expressed (in the manner described above) already in the 14th week of gestation. The stereological analysis of the number (Nv) and volume (Vv) of peritubular cells indicates a pulsatile development of these cells in the lamina propria of the human fetal testis. While the stereological variables determined for FL cells show a gradual decrease, the same variables determined for ML cells demonstrate a successive increase. It appears that the lamina propria of the fetal human testes shares many of the properties previously discovered in rodents.


Assuntos
Túbulos Seminíferos/citologia , Túbulos Seminíferos/embriologia , Contagem de Células , Colágeno/análise , Desmina/análise , Idade Gestacional , Humanos , Imuno-Histoquímica , Laminina/análise , Masculino , Túbulos Seminíferos/química , Testículo/química , Testículo/citologia , Testículo/embriologia
11.
Coll Antropol ; 25(1): 333-40, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11787559

RESUMO

The aim of the article is to investigate the development of blood and lymph systems in human parathyroid glands in prenatal and postnatal periods. The first capillaries are observed in these glands already in the lunar month 2. At the middle of pregnancy blood supply is increased, being extremely abundant in lunar months 9 and 10, as well as during the first year of life. As parts of the lymph system, intercellular lymph spaces are noticed in the parathyroid glands already in the lunar month 2, and also later, when lymph vessels are situated along the gland or in its connective capsule and within the gland parenchyma respectively. All these findings could be connected with the early function of these glands, as well as with the possibility that parathyroid hormone (PTH) is not transferred by blood only but by lymph as well.


Assuntos
Desenvolvimento Embrionário e Fetal , Sistema Linfático/embriologia , Glândulas Paratireoides/embriologia , Capilares/embriologia , Capilares/crescimento & desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , Sistema Linfático/crescimento & desenvolvimento , Masculino , Glândulas Paratireoides/irrigação sanguínea , Glândulas Paratireoides/crescimento & desenvolvimento , Hormônio Paratireóideo
12.
Coll Antropol ; 23(2): 737-44, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10646251

RESUMO

The article presents the investigation of histomorphological differentiation and growth of parathyroid glands in human fetus from the second to the ninth lunar month. The longer and the shorter diameter of these glands were measured. The obtained values are compared with the development and the growth intensity of the skeleton (biparietal head diameter and femoral length of a fetus from lunar months 3 to 9) and with the role of the placenta in the mentioned processes. The results of our investigation show the concordance of the skeletal growth with the development and histomorphological differentiation of these glands. The factors involved in these processes point out the complex relationship between the mother and fetus during osteogenesis, expressed on the hormonal level, in mineral metabolism and placental activity.


Assuntos
Osso e Ossos/embriologia , Desenvolvimento Embrionário e Fetal/fisiologia , Glândulas Paratireoides/embriologia , Antropometria , Humanos , Osteogênese , Placenta/fisiologia
13.
Lijec Vjesn ; 112(7-8): 258-61, 1990.
Artigo em Servo-Croata (Latino) | MEDLINE | ID: mdl-2292901

RESUMO

The article deals with the secretion of Sertoli cells. Different substances they secrete and their role in the testis are described. These cells release a number of factors in their environment, thus creating a local "milieu" and exerting a local control of spermatogenesis in the seminiferous tubules. As target cells for FSH and testosterone, Sertoli cells are also included in a systemic control of spermatogenesis, and because of that, they are necessary for the normal function of the male sex gland.


Assuntos
Células de Sertoli/metabolismo , Animais , Humanos , Masculino , Células de Sertoli/fisiologia
17.
Anat Histol Embryol ; 38(6): 461-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19793088

RESUMO

Sexual differentiation is a carefully regulated process that ultimately results in a development of the male or female phenotype. Proper development of the male phenotype is dependent upon the action of testosterone and anti-mullerian hormone. Leydig cells start to produce testosterone around day 12.5 in the fetal mouse testis, and continue to produce high levels of this hormone throughout gestation. In the present study, we examined whether expression of lanosterol 14alpha-demethylase (cyp51) and cytochrome P450 NADPH reductase, both involved in the cholesterol production, occurs simultaneously with proteins required for the production of steroid hormones. Immunocytochemical staining with the antibodies against cyp51, cytochrome P450 NADPH reductase, steroidogenic acute regulatory protein (StAR) and 3beta-hydroxysteroid dehydrogenase I (3beta-HSD I) was used to determine the ontogeny of expression of these four proteins. As expected, 3beta-HSD I and StAR proteins were detected on day 12.5 p.c., while expression of cyp51 and NADPH cytochrome P450 reductase appeared 1 day later, on day 13.5. Thereafter, the expression of all four proteins remained strong throughout gestation. Results of this study suggest that initial steps of steroid hormone production in murine Leydig cells are mostly dependent on exogenously derived cholesterol, while from day 13.5 onwards, mouse Leydig cells are able to synthesize cholesterol and are therefore not dependent on exogenous cholesterol resources.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Fosfoproteínas/metabolismo , Animais , Colesterol/biossíntese , Feminino , Maturidade dos Órgãos Fetais/fisiologia , Feto/embriologia , Idade Gestacional , Hormônios Esteroides Gonadais/biossíntese , Células Intersticiais do Testículo/fisiologia , Masculino , Camundongos , Gravidez , Esterol 14-Desmetilase
18.
Acta Anat (Basel) ; 155(3): 172-83, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8870785

RESUMO

The relation of the tests/testosterone with the structure and function of the mammalian parotid gland has so far been poorly investigated. The present study deals with the morphology of the rat parotid gland and its changes after orchiectomy and testosterone substitution. The glands of control and experimental animals (orchiectomized and orchiectomized with testosterone substitution) were analyzed by electron microscopy and stereology. In orchiectomized animals 30-60 days after castration, a significant reduction of the volume of the acini and the duct system as well as a significant increase of the connective tissue volume per cubic millimeter of the gland were noted. The volume and length of the intercalated and the striated ducts per cubic millimeter of parotid tissue are significantly reduced 45-60 days after orchiectomy. Excretory ducts seem to be unaffected by orchiectomy. The structure of the rat parotid acini is also changed by castration, indicating a reduction of acinar-cell activity. In controls, the volume of acinar cells with wide cisternae of rough endoplasmic reticulum is 3 times larger than the volume of acinar cells with regular and narrow cisternae of rough endoplasmic reticulum. After orchiectomy, the volume of acinar cells with wide cisternae of rough endoplasmic reticulum is significantly decreased, while the volume of acinar cells with regular and narrow cisternae of rough endoplasmic reticulum is significantly increased. Exogenously given testosterone can prevent or alleviate the mentioned effects of orchiectomy on the gland. It is concluded that orchiectomy affects the rat parotid gland, demonstrating the existence of an interaction between the testis and the mammalian parotid gland.


Assuntos
Glândula Parótida/ultraestrutura , Testículo/fisiologia , Testosterona/farmacologia , Animais , Masculino , Orquiectomia , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/crescimento & desenvolvimento , Ratos , Testosterona/sangue , Fatores de Tempo
19.
Arch Toxicol ; 67(2): 131-40, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8481101

RESUMO

The effects of exogenous testosterone on various testicular variables has become of increasing significance because of its potential use in male contraception. For this reason, high doses of two testosterone esters [testosterone propionate (TP) and testosterone enanthate (TE)] were used in a study of their influence on the morphology, length and curvature of the seminiferous tubules of the rat testis, and on cytological smears of the seminiferous tubules epithelium. TP was given for 14 days (3 mg/100 g body weight, i.m.) to assess the acute effects of testosterone on the seminiferous tubules. TE was administered for 60 days (in the same manner as TP) to study possible chronic effects on the rat testis. After TP and TE treatment the seminiferous tubule epithelium showed disorganization and desquamation of spermatogenic cells. In the TP-treated testes the tubules lined with Sertoli cells only were observed. The values for the length and curvature of seminiferous tubules of the TP- and TE-treated rats were significantly reduced (p < 0.001). All these changes were observed earlier in the TP-treated than in the TE-treated animals. In cytological smears of the testis of the TP- and TE-treated rats an increase of vacuoles and residual bodies in Sertoli cell cytoplasm was noted. In addition, a reduction of spermatogenic cells, particularly sperms, was manifest in the smears after treatment. Large groups of Sertoli cells were seen in the smears from these testes.


Assuntos
Túbulos Seminíferos/efeitos dos fármacos , Testosterona/análogos & derivados , Testosterona/farmacologia , Animais , Relação Dose-Resposta a Droga , Células Epiteliais , Epitélio/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Túbulos Seminíferos/anatomia & histologia , Túbulos Seminíferos/citologia , Células de Sertoli/efeitos dos fármacos , Testículo/anatomia & histologia , Testículo/citologia , Testículo/efeitos dos fármacos
20.
Int J Androl ; 19(5): 299-306, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8985779

RESUMO

In the testis, 'hyalinization' of the lamina propria of seminiferous tubules is often accompanied by similar changes within the walls of testicular blood vessels. The aim of our study was to investigate the structure of small blood vessels in hyalinized human testes by means of immunohistochemistry, electron microscopy and image analysis methods. Results of immunohistochemical analysis indicated that, despite hyalinization, testicular small blood vessels retained positive immunostaining for desmin and actin. Their basement membranes remained immunopositive for collagen IV and laminin. No proliferative (Ki-67) activity was observed in the blood vessel walls in testes from both control and infertile men. P-170 glycoprotein was found to be expressed only in primary spermatocytes. No difference in expression and localization of this antigen was observed between control and affected testes. Electron microscopy revealed a number of testicular arterioles with a notably narrow lumen due to enlarged endothelial cells in infertile men. Such arterioles also had a thickened subendothelial layer and an abundant tunica adventitia rich in connective tissue fibres and ground substance. Some venules in hyalinized testes displayed increased connective fibres and ground substance in the subendothelial layer, between the smooth muscle cells of the tunica media and the tunica adventitia. However, no changes were found in the capillary network, when compared to controls. Image analysis data showed a statistically significant increase in the surface of tunica intima and adventitia of arterioles and tunica media of venules. It is concluded that hyalinization mostly affects testicular arterioles and venules, but not capillaries. Our immunohistochemical data indicate that the 'nature' and/or extent of hyalinization in testicular small blood vessels differs from that described previously for the lamina propria of seminiferous tubules.


Assuntos
Infertilidade Masculina/fisiopatologia , Testículo/irrigação sanguínea , Adulto , Arteríolas/metabolismo , Arteríolas/ultraestrutura , Humanos , Imuno-Histoquímica , Infertilidade Masculina/metabolismo , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Testículo/metabolismo , Vênulas/metabolismo , Vênulas/ultraestrutura
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