Avaliação dos efeitos imediatos e tardios em testículos e pênis de ratos adultos submetidos ao estresse crônico por imobilização antes e após a puberdade

• Autor(a) principal: Ribeiro, Carina Teixeira
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/12327
• topic: Chronic stress; Morrphometric; Rat; Testicle; Penis; Testículo; Pênis; Pênis; Estresse crônico; Morfometria; Ratos; Testículo; Espermatogênese; Estresse; Camundongos; Imobilização; CNPQ::CIENCIAS BIOLOGICAS::MORFOLOGIA::ANATOMIA

The aim of this study was to investigate the effects of chronic stress on the testes and penis of prepubertal and adult rats and to assess possible alterations could be reversed when stress induction is ended. The animals were immobilized in opaque plastic cylinders for two hours daily for six weeks. Seventy six rats were assigned into eight groups depending on the type of treatment (control or stressed), of the age at which the stress was initiated (prepubertal, 4 weeks of age) or (adult, 10 weeks of age), and the time of evaluation (immediate or late). The stressed animals for immediate evaluation (ECI4, n = 10 and ECI10, n = 9) were analyzed 24 hours after the last stressor stimulus, whereas the stressed animals for late evaluation (ECT4, n = 10 and ECT10, n = 9) were analyzed six weeks after the last stressor stimulus. Other animals the same age were used as controls (CI4, CT4, CI10 and CT10) kept free, without food and water for the same period of the animals of the stressed groups. Experiment approved under protocol CEUA/004/2015. The animals were weighed before and after the end of treatment. Before the death of the animal, the blood was collected for analysis of the testosterone and the spermatozoa collected from the tail of the epididymis for evaluation of concentration, motility and viability. The testes were fixed in Bouin for 24 hours and postfixed in 3.7% formaldehyde, processed in paraffin blocks and stained by H&E. The sections were photographed at different magnifications for analysis of the seminiferous tubule diameter, height of the seminiferous epithelium, volume density and absolute volume of the seminiferous and stromal structures. The penis was fixed in 3.7% formaldehyde and its mid-shaft was used for histomorphometric analysis. Cross sections of this region were stained with Masson's Trichomic to evaluate the area of the corpus cavernosum (with and without the tunica albuginea), area of the tunica albuginea and densities of the cavernous structures. It was stained with Weigert's resorcin-fuchsin with previous oxidation to evaluate the elastic system fibers. The data were organized and the mean of each group were analyzed and compared by Student's t-test. The rats of the ECI4 group had a reduction in body weight and diameter of the seminiferous tubules. The rats of the ECI10 group showed several functional and morphological (testicular weight, diameter of the seminiferous tubules and structures of the corpora cavernosa) reductions. The rats in the ECT4 group showed increased body weight and of intertubular compartment volumetric and absolute densities and reducing tubular compartment volumetric density and fibers of the elastic system in the corpus cavernosum. The ECT10 group presented reduction of sperm viability and increased area of the tunica albuginea of penis. The chronic stress induced changes in testicles and penises before and after puberty. Nevertheless, the alterations were more significant when the stress stimuli were induced in adulthood; however, these animals recovered almost completely after a long time without stress. Already in the prepubertal animals the alterations appear permanents.