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- ItemAcesso aberto (Open Access)Androgens and the male reproductive tract: an overview of classical roles and current perspectives(Sociedade Brasileira de Endocrinologia e Metabologia, 2009-11-01) Patrão, Marilia T. C. C. [UNIFESP]; Silva, Erick J. R. [UNIFESP]; Avellar, Maria Christina Werneck [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Androgens are steroid hormones that play key roles in the development and maintenance of male phenotype and reproductive function. These hormones also affect the function of several non-reproductive organs, such as bone and skeletal muscle. Endogenous androgens exert most of their effects by genomic mechanisms, which involve hormone binding to the androgen receptor (AR), a ligand-activated transcription factor, resulting in the modulation of gene expression. AR-induced non-genomic mechanisms have also been reported. A large number of steroidal and non-steroidal AR-ligands have been developed for therapeutic use, including the treatment of male hypogonadism (AR agonists) and prostate diseases (AR antagonists), among other pathological conditions. Here, the AR gene and protein structure, mechanism of action and AR gene homologous regulation were reviewed. The AR expression pattern, its in vivo regulation and physiological relevance in the developing and adult testis and epididymis, which are sites of sperm production and maturation, respectively, were also presented.
- ItemSomente MetadadadosAvaliação do tratamento crônico com resveratrol sobre níveis glicêmicos e parâmetros reprodutivos de ratos com diabetes tipo 1 induzida pela estreptozotocina na pré-puberdade(Universidade Federal de São Paulo (UNIFESP), 2014-12-18) Simas, Joana Nogueres [UNIFESP]; Valdeolivas, Sandra Maria Miraglia Valdeolivas [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Aims/hypothesis: In Diabetes Mellitus, the persistent hyperglycemia unleashes the progression of several complications including the overproduction of reactive oxygen species and reproductive alterations. Resveratrol (RES) is antioxidant and antiapoptotic. We assessed the trilogy: type-1 Diabetes (DM1), male reproduction and RES-treatment. Methods: Eighty-four prepubertal male rats were distributed into 7 groups: sham-control (SC); RES-treated (R);resveratrol-vehicle-treated (RV); diabetic (D); diabetic-insulin-treated (DI); diabetic-RES-treated (DR), diabetic-insulin and RES-treated (DIR). DM1 was induced by a single intraperitoneal streptozotocin (STZ) injection (65 mg/kg) on the 30th day postpartum (dpp). Animals of DR, DIR and R groups received 150mg/day of RES by gavage for 42 consecutive days (from the 33 dpp). DI and DIR rats received subcutaneous injections of insulin (1U/100g bw/day) from the 5th day after the DM1 induction. The blood-glucose-measurement (BGM) of rats was obtained at 5 different time-points: before the STZ-treatment, at 33, 45, 64 and 75 dpp when they were submitted to euthanasia for morphometric and biometric testicular analyses, spermatic evaluation and hormonal dosages. Results: In the D group, BGM was higher than in DR, DI and DIR. Besides, morphometric testicular measurements and testosterone and estradiol dosages were lower than in DR and DIR; LH-dosage was also lower than in DR. The preputial-separation age was delayed in diabetes-induced groups. The DR and DIR groups showed an improvement of the sperm mitochondrial activity, epididymal sperm counts and of the frequency of morphologically normal sperms. Conclusions/interpretation: RES improved glycemia, sperm quantitative and qualitative parameters and hormonal profile in DM1-induced Rats.
- ItemSomente MetadadadosAvaliação reprodutiva tardia da prole exposta à nicotina durante as fases de prenhez e lactação(Universidade Federal de São Paulo (UNIFESP), 2014-07-30) Silva, Mayra Miranda Rodrigues da [UNIFESP]; Valdeolivas, Sandra Maria Miraglia Valdeolivas [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Introduction: About 1/3 of the population smokes. The nicotine found in cigarettes, reaches breast milk and crosses the placental membrane. Previously, it was observed that nicotine administered to female rats during pregnancy and lactation, causes morphofunctional alterations Leydig cells and overt damage of the seminiferous epithelium of the offspring. Objective: To evaluate the spermatogenic damage, previously observed in offspring at 90 days of age, from pregnant rats and exposed infants to nicotine, are held or aggravated after up to two full terms of spermatogenesis (53 + 53 days). Methods: Rats were exposed to nicotine (2 mg / kg / day) throughout pregnancy and lactation, using a subcutaneous osmotic minipump implantation (C) performed in each of these periods. Control groups "sham" (CS, with subcutaneously implanted minipumps, but containing 0.9% saline) and absolute (CA without implants) were established. The offspring were euthanized at 90, 143 and 196 days postpartum (subgroups). Testicular parameters, reviews and sperm and testosterone plasma levels and cholesterol intratesticular were investigated. Results: The progenies showed significant changes of biometric parameters, morphometric and stereological testicular, in all subgroups. Histopathology showed in rats of all subgroups nicotine, normal characteristics of the seminiferous epithelium, except for the more exacerbated peeling germ cells into the lumen, observed in these animals. Quantitative evaluation and sperm plasma levels and cholesterol and testosterone intratesticular no significant changes. However, the offspring of the subgroups nicotine exhibited high frequency of morphologically abnormal sperm and reduced sperm motility of these gametes. A significant loss of mitochondrial activity and an increase in sperm DNA fragmentation (comet assay) were observed in these animals. Conclusions: The results indicate reproductive harm late in the offspring, concerning the quality of the epididymal sperm tail, due to exposure of rats to nicotine in pregnancy and lactation.