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O presente estudo foi realizado com o intuito de relatar a ocorrência e morfologia de células pigmentares viscerais constituintes do "sistema pigmentar extracutâneo" em Physalaemus nattereri (Steindachner, 1863) (Leptodactylidae). Foram utilizados dez exemplares machos para a análise macroscópica e obtenção de fragmentos testiculares incluídos em resina e corados com H/E. Os anuros, dentre outros animais exotérmicos, possuem células especiais, os melanócitos, que se caracteriza por intensa pigmentação e sintetiza melanina, além de melanomacrófagos, que se caracteriza por atividade fagocítica e muitas vezes apresentam intensa pigmentação. A nomenclatura destas células não é consensual e, por isso, várias denominações são apresentadas, principalmente nos seguintes órgãos: fígado (como sinônimo de células de Kupffer), rins, baço e menos freqüentemente em outras localizações, com os termos - células pigmentares, células pigmentares extracutâneas, macrófagos pigmentados, melanomacrófagos, melanófagos, melanóforos e melanócitos. Para os anuros os estudos são recentes e relatam células pigmentares em poucas espécies. Em Physalaemus nattereri e alguns anuros, os pigmentos melânicos são encontrados, além da cútis, em outros órgãos constituindo um sistema pigmentar extracutâneo, com diferentes ocorrências, tipos e quantidade em distintas espécies. Associados ao aparelho reprodutor de P. nattereri, os melanócitos foram observados nas gônadas, na albugínea e no interstício, especialmente associado com vasos sangüíneos. A notória presença de numerosas células com pigmento distribuídas no testículo confere uma coloração que varia do preto mesclado com branco ao preto intenso. Trata-se de uma rara peculiaridade e não há informações sobre seu significado funcional ou valor biológico.

In amphibians, pigmented cells are present in several organs, composing an extracutaneous pigmentary system. Seventeen species from two families were studied to develop a protocol for pigmentary classification. The amount and distribution of these cells are variable, allowing the establishment of anatomical patterns for visceral pigmentation in anuran testes.

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Melanomacrophages are the pigmented cells present in the hematopoietic organs. Besides melanin, hemosiderin and lipofuscin are also observed in the melanomacrophages. For the liver, however, numerous studies relate these cells to immunological and metabolic functions. Therefore, the aim of this study is to evaluate the hepatic metabolism by quantifying melanin, hemosiderin and lipofuscin in the anuran Eupemphix nattereri submitted to varying thermal conditions. E. nattereri adult males were separated into three groups, as follows: (i) five animals in the control group were kept at room temperature (27 C); (ii) 30 animals were submitted to hyperthermic (35.1 C); and (iii) 30 to hypothermic (18.9 ) conditions. In each experiment, the animals were analyzed and separated into two different treatments:(1) immediately after undergoing the stress; and, (2) after recovering from the stress caused by the stimulus, at three distinct times (12 hr, 24 hr, and 48 hr). Both hyperthermia and hypothermia decreased hepatic pigmentation after thermal stress. The recovered animals of both experimental treatments showed as much pigmentation as the control animals. Thermal stress alters hemosiderin and lipofuscin as well, which may be related to liver function catabolism. In conclusion, liver pigmentation decreased due to temperature variation and duration of thermal stimulation to which the animals were exposed. The increase in temperature rather than hypothermia led to more drastic physiological disorders. In this study, we observed that thermal stress for a short period compromises the morphology and liver function, as observed by the changing pigmentation of melanomacrophages. These analyses can be used as biomarkers of environmental effects. Anat Rec,

Ectothermic vertebrates have a well-developed system of melanincontaining cells, which localize in several organs and tissues and compose an extracutaneous pigmentary system. This research aimed at characterizing histological and ultrastructural patterns of pigmented cells in the testes of the anura Eupemphix nattereri (Steindachner, 1963), including the stereological and quantitative evaluation of this cell type in the gonads. Ten adult males were collected in Nova Itapirema, Sã o Paulo, Brazil, and submitted to morphological studies with light and transmission electron microscopy. The testis presents a great number of large cells with many brown granules and long cytoplasmic processes. The pigmented cells found in the testis are structurally similar to melanocytes, characterized by large amounts of melanosomes. The cells may be in intimate contact with the same cell type, with myoid cells surrounded by a large amount of collagen fibers, Leydig cells, and next to fibroblasts. The distribution and amount of extracutaneous melanocytes is variable when other organs and membranes are analyzed, allowing the establishment of species-specific patterns for the extracutaneous pigmentary system. Anat Rec, 290:795-800, 2007Rec, 290:795-800, . 2007 Wiley-Liss, Inc.

Provete, D. B, Franco‐Belussi, L., de Souza Santos, L. R., Zieri, R., Moresco, R. M., Martins, I. A., de Almeida, S. C., & de Oliveira, C. (2012). Phylogenetic signal and variation of visceral pigmentation in eight anuran families. —Zoologica Scripta, 41, 547‐556.Visceral pigmentation is found in several organs and structures of ectothermic animals, comprising the extracutaneous pigmentary system. Its function is not well defined, although it is known that melanin is produced and stored inside pigmented cells. Previous studies demonstrated that the distribution of visceral pigmentation is neither homogeneous among organs among anuran species. We described the diversity of visceral pigmentation in 12 organs/structures from 32 anuran species belonging to eight families in a phylogenetic context. We also determined in which node(s) of the phylogeny there is more variation in the pigmentation and whether this variation has phylogenetic signal. The visceral pigment cells in organs and structures of the abdominal cavity varied among genera. All species had pigmentation in the urogenital and cardiorespiratory systems, whereas the stomach lacks pigmentation in all species. We also found a phylogenetic signal for pigmentation in all organs and structures taken together, besides heart, testes, lumbar parietal peritoneum and lumbar nerve plexus when considered separately. Overall, considering all organs, the highest diversity of categories of pigmentation was found in the nodes corresponding to Cruciabatrachia and Athesphatanura. This study constitutes the first step towards understanding the evolution of visceral pigmentation in anurans.

Rubber trees are easily recognizable for being woody, medium to large-sized plants, having a typical deciduous behavior, and especially because they produce latex. The purpose of this work was to study the anatomy and morphology of the leaf, comparing rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell.-Arg.] clones (RRIM 600 and GT 1) grafted on the same root stock (Tjir 1), grown under the same climatic and soil conditions. This study allowed clones to be differentiated and also provided information on the location and disposition of laticifers in the leaf tissue. Cross sections of the mesophyll, center ribbing and petiole regions were made, followed by usual permanent histological blade methods. Biometric analyses of tissue extensions in the palisade and spongy parenchymas were carried out, and the number of cells in the spongy parenchyma were counted. At the same time, biometrical analyses were made for stomata. The comparison between the clones showed that there were no significant differences in epidermal cell height, spongy parenchyma height, number of cells in the spongy parenchyma layer, and size and width of leaflets. However, variation was observed for cell thickness in the palisade parenchyma. The clone GT1 presented greater thickness as compared to the RRIM 600 clone. GT1 had also a greater number of stomata in comparison to RRIM 600, but they were smaller. GT1 presented greater petiole and center ribbing diameters in the leaves and a greater amount of sclerenchyma fibers than RRIM 600. Key words: Hevea brasiliensis, leaf, clones ANATOMIA FOLIAR DE CLONES DE SERINGUEIRARESUMO: A seringueira é uma planta de fácil reconhecimento por ser lenhosa, de porte mediano a grande, que apresenta um padrão característico de desfolha e reenfolhamento e, sobretudo, pela produção de látex. O objetivo do trabalho foi efetuar um estudo anatômico e morfológico foliar, comparando os clones RRIM 600 e GT 1 de seringueira [Hevea brasiliensis (Wild. ex Adr. de Juss.) Muell.-Arg], desenvolvidos sob as mesmas condições edáficas e climáticas, para obtenção de informações que possam fornecer subsídios para correlações com dados fisiológicos e também diferenciar os clones em relação ao conteúdo de fibras, espessamento de tecidos do parênquima paliçádico e do parênquima lacunoso, caracterização anatômica do pecíolo, número e tamanho de estômatos e fornecer dados referentes a morfologia foliolar. Foram realizadas secções transversais na região do mesófilo, nervura central e pecíolo, seguindo-se os métodos usuais de preparação de lâminas permanentes. Foram realizadas análises biométricas de extensões de tecidos dos parênquimas paliçádico e lacunoso e contagem do número de células do parênquima lacunoso. Paralelamente foram realizadas análises biométricas para aferições de estômatos. Não houve diferenças para a altura das células epidérmicas, altura e número de camadas do parênquima lacunoso e para o comprimento e para a maior largura do limbo foliolar. Porém houve variação para a espessura das células do par...