RESUMO

The epidermis of Ostariophysi fish is composed of 4 main cell types: epidermal cells (or filament containing cells), mucous cells, granular cells and club cells. The morphological analysis of the epidermis of the catfish Pimelodella lateristriga revealed the presence of only two types of cells: epidermal and club cells. The latter were evident in the middle layer of the epidermis, being the largest cells within the epithelium. Few organelles were located in the perinuclear region, while the rest of the cytoplasm was filled with a non-vesicular fibrillar substance. Club cells contained two irregular nuclei with evident nucleoli and high compacted peripheral chromatin. Histochemical analysis detected prevalence of protein within the cytoplasm other than carbohydrates, which were absent. These characteristics are similar to those described to most Ostariophysi studied so far. On the other hand, the epidermal cells differ from what is found in the literature. The present study described three distinct types, as follows: superficial, abundant and dense cells. Differences among them were restricted to their cytoplasm and nucleus morphology. Mucous cells were found in all Ostariophysi studied so far, although they were absent in P. lateristriga, along with granular cells, also typical of other catfish epidermis. The preset study corroborates the observations on club cells' morphology in Siluriformes specimens, and shows important differences in epidermis composition and cell structure of P. lateristriga regarding the literature data.

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RESUMO

The occurrence of seasonality in bullfrog (Lithobates catesbeianus) spermatogenesis was analyzed by quantifying germ cell populations throughout the year, which were divided into bimesters, from November 2001 to October 2002. Body weight, liver weight, fat body weight and gonadal weight were taken and bimonthly grouped. Using these data, the gonadosomatic, hepatosomatic, and liposomatic indexes were calculated. All animals were kept in the same cement cages in a frog farm, and sampled every month. The cages were underthe influence of climate variables changes, such as photoperiod, temperature, rainfall and relative humidity.Body weight was higher during Spring and Summer, and a significant reduction has occurred between Julyand August. The highest gonadosomatic index values were registered from May to October, coinciding withthe period of gonadal preparation for reproduction. Also, the reproduction of bullfrog is directly related toenvironmental factors, mainly due to Summer and Winter humidity variations.

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The present study was carried out to investigate the effects of Rudgea viburnoides infusion on the body biometry and testicular morphometry and stereology of adult Wistar rats. Two groups received the infusion daily at the concentration of 3 or 6 mg/mL for 40 days. The control group received only water. Neither the biometrical parameters nor the tubular diameter and the height of the seminiferous epithelium showed any significant alterations in the treated animals. Leydig cells stereology did not show any significant alterations in the treated animals. These results indicated that R. viburnoides did not cause alterations in body biometry and testicular morphometry.

RESUMO

The aim of this study is to investigate the association of a single low dose of Cd and daily doses of Ginkgo biloba extract (GbE) on the testis and accessory glands of rats. The animals were treated with a single dose of 3 µmol/kg body weight of cadmium chloride (CdCl2) and/or 100 mg/kg body weight of GbE. The plasma testosterone levels; corporal, testicular, and accessory glands weight; gonadosomatic index, volumetric proportion; and absolute volume of testicular components did not change after the treatments. CdCl2 caused significant reduction in Leydig cells volume and altered Leydig cell morphology, as well as vacuolated Sertoli cells cytoplasm, irregular chromatin condensation of late spermatids, and modified acrosome formation. However, animals that received GbE did not show these alterations. The reversal of Cd-induced alterations by the extract is a strong indication that G. biloba is helpful in diminishing the effect of Cd toxicity.

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Guaraná (Paullinia cupana) is an Amazonian plant. Its antioxidant potential was demonstrated to be due to the high polyphenol concentration. On the other hand, one of the mechanisms underlying cadmium-induced cellular damage is free radical mediated, resulting in increased oxidative processes. This study investigated P. cupana's potential to attenuate cadmium-induced damages in Wistar rat testis. Adult male Wistar rats were either pre-treated with 2 mg/g body weight (BW) of powdered P. cupana seed during 56 days and/or injected with cadmium chloride at a dose of 1.15 mg/kg BW. After cadmium exposition (48 h), testes samples were evaluated by histological and stereological analyses. Both groups exposed to cadmium presented evident morphological alterations relative to control animals. A few rodents showed massive cell death in the seminiferous epithelium and intertubular space, indicating that some animals are more sensitive to cadmium. Despite the alterations observed in both groups, pre-treatment with P. cupana was effective in attenuating morphological changes in Leydig cells, as well as reducing inflammatory response, relative to animals exclusively exposed to the metal. Animals treated only with P. cupana presented a significant increase in plasma testosterone levels and a significant increase in volumetric proportions of seminiferous tubules, which are indicative of spermatogenic stimulation.

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RESUMO

This study was carried out to evaluate the effects of Arctium lappa L. (burdock) on the liver of adult male Wistar rats as measured by light microscopy and biochemical parameters. The rats received the extract in water bottles at doses of 10 or 20 g/L daily for 40 days. There were no significant changes in the plasma levels of albumin, aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyl transferase (GGT), total protein, total cholesterol, urea, uric acid, triacylglycerol, calcium, phosphorus, chlorine and direct bilirubin. The morphological analysis did not reveal histopathological alterations in liver tissue. Both biochemical and morphological data did not indicate A. lappa toxicity.

A bardana (Arctium lappa L) é uma planta trazida do Japão e aclimatada no Brasil, e é extensamente utilizada na medicina popular em todo mundo. Este estudo foi realizado para avaliar os possíveis efeitos da A. lappa no fígado e nos parâmetros bioquímicos plasmáticos em ratos Wistar adultos. Estes receberam a infusão de bardana nas doses de 10 ou 20 g de folhas secas /L de água, por 40 dias. Não houve alteração significativa nos níveis plasmáticos de albumina, aspartato transaminase (AST), alanina transaminase (ALT), gamma glutamil transferase (GGT), proteínas totais, colesterol total, uréia, ácido úrico, triglicérides, cálcio, fósforo, bilirrubina direta e cloro. A análise morfológica não revelou alterações histopatológicas no fígado. Os dados bioquímicos e morfológicos não indicaram a toxicidade da bardana.

RESUMO

Rudgea viburnoides leaves are widely used in popular Brazilian medicine as a diuretic, antirheumatic, hypotensive and blood depurative tea. The present study was carried out to investigate the effects of this infusion on the liver and on the plasma biochemical parameters of Wistar rats. Two groups received the R. viburnoides leaf infusion at a daily dose of 10 or 20g dry-leaves/L water, during 40 days. The histopathological analysis did not show degenerated areas or infiltration of leucocytes. Hepatic morphometry showed accumulation of fat in the hepatocytes of the treated groups. There was no significant change in the plasma levels of urea, creatinin, uric acid, direct bilirubin, cholesterol, total proteins, albumin, gamma glutamyl tranferase (gamma-GT), alanine transaminase (ALT), aspartate transaminase (AST), chlorine, phosphate and calcium. A significant reduction in the plasma levels of triacylglycerol (TAG) occurred in the group that received the higher dose.

As folhas de Rudgea viburnoides Benth. são utilizadas na medicina popular como diuréticas, hipotensoras, anti-reumáticas, depurativas do sangue e em regimes de emagrecimento. O presente estudo foi delineado para avaliar o efeito da infusão das folhas de R. viburnoides nos parâmetros bioquímicos plasmáticos e na morfologia e morfometria hepática de ratos Wistar adultos. Dois grupos receberam a infusão das folhas, diariamente, nas dosagens de 10 e 20 g de folhas secas/L de água, durante 40 dias. O grupo controle recebeu a mesma quantidade de água. As análises histopatológicas não mostraram áreas degeneradas e infiltrados inflamatórios. A morfometria hepática mostrou acúmulo significativo de gordura nos hepatócitos dos animais tratados, principalmente no grupo que recebeu a maior dose da infusão (8,75 por cento de gotículas lipídicas), comparado com 0,25 por cento delas encontradas nos animais controles. Não foram observadas alterações nos níveis plasmáticos de uréia, creatinina, ácido úrico, bilirrubina direta, colesterol, proteínas totais, albumina, gama-glutamil transferase (GGT), alanina transaminase (ALT), aspartato transaminase (AST), cloro, fósforo e cálcio. Foi observada redução significativa de 20,6 por cento nos níveis plasmáticos de triacilglicerol no grupo que recebeu a infusão mais concentrada, comparada aos animais controle.