The expression of aquaporins 1 and 9 in adult rat epididymis is perturbed by chronic exposure to ethanol

Aquaporins (AQPs), notably AQP-1 and AQP-9, may contribute to reabsorption of fluid and solute across the epididymis. Ethanol is related to be a toxicant affecting directly or indirectly the epididymis and the sperm motility. This study examined the expression of AQP-1 and AQP-9 in adult epididymis of the UChA and UChB 10% (v/v) ethanol-preferring rats, focusing the ethanol-induced hormonal disturbances upon the regulation of these AQPs. Chronic ethanol intake significantly decreased body weight, while UChA and UChB rats displayed a marked loss of epididymal weights. Both ethanol-consuming animals had a severe reduction of testosterone levels, whereas LH and 17β-estradiol were unchanged. Throughout the epididymis, a strong reaction to AQP-1 was observed in myoid and endothelial cells of the UChB ethanol-preferring rats, differently from a moderate intensity in the initial segment of the UChA rats. In addition, AQP-9 showed a strong immunoreaction in the apical membrane of principal cells at initial segment. In cauda epididymis, the level of AQP-9 was reduced along the microvillus projections in both UChA and UChB rats compared to controls. We conclude that chronic ethanol consumption modulates the androgen levels, thereby modifying the expression pattern of AQP-1 and 9 in the epididymis. © 2011 Elsevier Ltd.

Bothropstoxin-I reduces evoked acetylcholine release from rat motor nerve terminals: Radiochemical and real-time video-microscopy studies

Understanding the biological activity profile of the snake venom components is fundamental for improving the treatment of snakebite envenomings and may also contribute for the development of new potential therapeutic agents. In this work, we tested the effects of BthTX-I, a Lys49 PLA2 homologue from the Bothrops jararacussu snake venom. While this toxin induces conspicuous myonecrosis by a catalytically independent mechanism, a series of in vitro studies support the hypothesis that BthTX-I might also exert a neuromuscular blocking activity due to its ability to alter the integrity of muscle cell membranes. To gain insight into the mechanisms of this inhibitory neuromuscular effect, for the first time, the influence of BthTX-I on nerve-evoked ACh release was directly quantified by radiochemical and real-time video-microscopy methods. Our results show that the neuromuscular blockade produced by in vitro exposure to BthTX-I (1 μM) results from the summation of both pre- and postsynaptic effects. Modifications affecting the presynaptic apparatus were revealed by the significant reduction of nerve-evoked [3H]-ACh release; real-time measurements of transmitter exocytosis using the FM4-64 fluorescent dye fully supported radiochemical data. The postsynaptic effect of BthTX-I was characterized by typical histological alterations in the architecture of skeletal muscle fibers, increase in the outflow of the intracellular lactate dehydrogenase enzyme and progressive depolarization of the muscle resting membrane potential. In conclusion, these findings suggest that the neuromuscular blockade produced by BthTX-I results from transient depolarization of skeletal muscle fibers, consequent to its general membrane-destabilizing effect, and subsequent decrease of evoked ACh release from motor nerve terminals. © 2012 Elsevier Ltd.

Long-term effects of perinatal androgenization on reproductive parameters of male rat offspring androgenization and male rat reproduction

It is known that during sex differentiation, fetal androgens are critical determinants of the male phenotype. Although testosterone is necessary for normal development of male sexual behavior, perinatal androgen treatment can result in disruption of normal male sexual reproduction. Pregnant Wistar rats were administered either corn oil (vehicle) or testosterone propionate at 0.2 mg/kg from gestational day 12 until the end of lactation and the reproductive function of male offspring was evaluated at 90 (adulthood) and 270 (middle age) days of age. Perinatal androgenization in the rat provoked a reduction in sperm production and reserves in adulthood that did not affect fertility and did not persist at more advanced ages, as shown by the results at post-natal day 270. If perinatal androgenization promotes similar effects in humans of reproductive age, the results of the present work can impact male reproduction health, given the less efficient spermatogenesis and lower sperm reserves in the human epididymis, compared to rodents. © Georg Thieme Verlag KG Stuttgart. New York.

NF-kB overexpression and decreased immunoexpression of AR in the muscular layer is related to structural damages and apoptosis in cimetidine-treated rat vas deferens

Background: Cimetidine, histamine H2 receptors antagonist, has caused adverse effects on the male hormones and reproductive tract due to its antiandrogenic effect. In the testes, peritubular myoid cells and muscle vascular cells death has been associated to seminiferous tubules and testicular microvascularization damages, respectively. Either androgen or histamine H2 receptors have been detected in the mucosa and smooth muscular layer of vas deferens. Thus, the effect of cimetidine on this androgen and histamine-dependent muscular duct was morphologically evaluated.Methods: The animals from cimetidine group (CMTG; n=5) received intraperitoneal injections of 100 mg/kg b.w. of cimetidine for 50 days; the control group (CG) received saline solution. The distal portions of vas deferens were fixed in formaldehyde and embedded in paraffin. Massońs trichrome-stained sections were subjected to morphological and the following morphometrical analyzes: epithelial perimeter and area of the smooth muscular layer. TUNEL (Terminal deoxynucleotidyl-transferase mediated dUTP Nick End Labeling) method, NF-kB (nuclear factor kappa B) and AR (androgen receptors) immunohistochemical detection were also carried out. The birefringent collagen of the muscular layer was quantified in picrosirius red-stained sections under polarized light. The muscular layer was also evaluated under Transmission Electron Microscopy (TEM).Results: In CMTG, the mucosa of vas deferens was intensely folded; the epithelial cells showed numerous pyknotic nuclei and the epithelial perimeter and the area of the muscular layer decreased significantly. Numerous TUNEL-labeled nuclei were found either in the epithelial cells, mainly basal cells, or in the smooth muscle cells which also showed typical features of apoptosis under TEM. While an enhanced NF-kB immunoexpression was found in the cytoplasm of muscle cells, a weak AR immunolabeling was detected in these cells. In CMTG, no significant difference was observed in the birefringent collagen content of the muscular layer in comparison to CG.Conclusions: Cimetidine induces significant damages in the epithelium; a possible antiandrogenic effect on the basal cells turnover should be considered. The cimetidine-induced muscle cells apoptosis confirms the susceptibility of these cells to this drug. The parallelism between enhanced cytoplasmic NF-kB immunolabeling in the damaged muscular tissue and muscle cell apoptosis suggests that this drug may avoid the translocation of NF-kB to the nucleus and interfere in the control of NF-kB-mediated smooth muscle cell apoptosis. The decreased immunoexpression of ARs verified in the damaged muscular tissue reinforces this possibility. © 2013 Koshimizu et al.; licensee BioMed Central Ltd.

Surface Roughness of Acrylic and Silicone-Based Soft Liners: In Vivo Study in a Rat Model

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of the treatment of root surface-adhered necrotic periodontal ligament with propolis or fluoride in delayed rat tooth replantation

Objectives: The purpose of this study was to evaluate the application of 15 % propolis and 2 % acidulated-phosphate sodium fluoride solutions on the root surface-adhered necrotic cemental periodontal ligament in delayed tooth replantation. Materials and methods: Thirty Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. After this period, the dental papilla, enamel organ, and pulp tissue were removed, and the animals were randomly assigned to three groups: group I = immersion in saline for 10 min; group II = immersion in a 2 % acidulated-phosphate sodium fluoride solution for 10 min; and group III = immersion in a 15 % propolis and propylene glycol solution for 10 min. The root canals were filled with a calcium hydroxide paste and the teeth were replanted. Results: Inflammatory resorption, replacement resorption, and ankylosis were observed in all groups without a statistically significant difference (p > 0.05) among them. Conclusions: Under the tested conditions, the application of fluoride or propolis on root surface-adhered necrotic periodontal ligament did not favor the healing process in delayed tooth replantation. © 2013 Springer-Verlag Berlin Heidelberg.

Marcadores da síndrome metabólica e da capacidade aeróbia de ratos (Rattus Norvegicus Albinus, Wistar) em diferentes idades: efeito do exercício

Pós-graduação em Ciências da Motricidade - IBRC

Carcinogênese quimicamente induzida por DMBA em glândulas salivares submandibulares de ratos (rattus norvegicus)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação histológica e histomorfométrica do reparo ósseo em tíbias osteotomizadas de ratos (Rattus novergicus albinus) frente à ausência de carga e tratamento com ultrassom

Pós-graduação em Ciência Animal - FMVA

Ação imunomodulatória da β-glucana e Saccharomyces cerevisiae em ratos (Rattus rattus) da linhagem Wistar imunossuprimidos pela administração experimental de dexametasona

Pós-graduação em Medicina Veterinária - FCAV

Efeito do ultra-som terapêutico sobre o crescimento ósseo das epífises, distal do fêmur e proximal da tíbia em Rattus novegicus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Alterações histológicas do miocárdio, rim e fígado de ratos (Rattus novergicus) Wistar submetidos à infusão de angiotensina II: influência na função ventricular esquerda e resposta ao tratamento com losartan e carvedilol

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Parâmetros biofísicos, bioquímicos e imunohistoquímicos de fêmures de Rattus novergicus albinus em diferentes idades para padronização de valores de referência estática e dinâmica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Uso de antiinflamatórios COX-2 seletivos em ratos (Rattus novergicus) Wistar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Infecção experimental de ratos (Rattus norvegivus) da linhagem Lewis por Strongyloides venezuelensis: dinâmica da infecção, uso de PCR para detecção do parasita e caracterização da resposta imune humoral

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)