Revisión histórica, distribución potencial y estado de conservación de la rata endémica de México Xenomys nelsoni (Rodentia: Cricetidae) / Historical review, potential distribution, and conservation of the Mexican endemic rat Xenomys nelsoni (Rodentia: Cricetidae)

Resumen Introducción: La Rata de Magdalena, Xenomys nelsoni, es un roedor endémico de México, de distribución restringida a las selvas bajas caducifolias densas, en una pequeña región de la costa del Pacífico mexicano. Es una especie poco conocida, catalogada como "En Peligro" de acuerdo con la Unión Internacional para la Conservación de la Naturaleza (IUCN). Este desconocimiento unido a la alta tasa de deforestación de su hábitat hace que su conservación sea prioritaria. Objetivo: Realizar un recuento histórico de los registros depositados en las colecciones científicas, generar mapas de distribución potencial y analizar el estado de conservación de la especie. Método: Los datos de ocurrencia de las especies se obtuvieron de la literatura y bases de datos digitales y se analizaron por décadas. Se utilizaron los programas GARP y MaxEnt para generar los modelos de nicho ecológico. La importancia de las variables en el modelo se estimó mediante un análisis Jackknife. Resultados: A lo largo de 129 años 19 recolectores registraron 69 ejemplares, de los cuales 65 están depositados en siete colecciones internacionales y una nacional. Aunque la especie sólo se ha recolectado en Jalisco y Colima, la distribución potencial de X. nelsoni incluye también el estado de Michoacán. De esta área estimada, sólo el 1.5 % se encuentra dentro de un Área Natural Protegida. Conclusiones: Los resultados de la distribución potencial podrían ser utilizados para verificar la presencia de la especie en lugares donde no ha sido recolectada como el norte de la Reserva de la Biosfera Chamela-Cuixmala y en algunas zonas de la provincia fisiográfica Costas del Sur en el estado de Michoacán. Es necesario incrementar los muestreos en regiones poco estudiadas predichas por el modelo y aumentar el área de protección.

Abstract Introduction: The Magdalena Rat, Xenomys nelsoni, is a rodent endemic to Mexico, whose distribution is restricted to dense tropical dry forests in a small region on the Pacific coast of Mexico. It is a poorly known species categorized as "Endangered" by the International Union for Conservation of Nature (IUCN). This lack of knowledge and the high rates of deforestation of its habitat makes its conservation a priority. Objective: To summarize the historical records deposited in scientific collections, to create potential distribution maps, and to analyze the conservation status of the species. Methods: We obtained species occurrence data from literature and digital databases, analyzing them by the decade. We used GARP and MaxEnt software to generate the ecological niche models. The importance of the variables in the model was estimated using the Jackknife technique. Results: Over 129 years, 19 collectors registered 69 specimens, of which 65 are deposited in one national and seven international collections. Although the species has only been collected in Jalisco and Colima, the potential distribution for X. nelsoni also includes the state of Michoacán. Of this estimated area, only 1.5 % is in a Protected Natural Area. Conclusions: The results of the potential distribution could be used to verify the presence of the species in places where it has not been collected, such as the northern part of the Chamela-Cuixmala Biosphere Reserve and in some areas of the physiographic province Costas del Sur in the state of Michoacán. It is needed to increase samplings in the least studied regions predicted by the model and expand the area of protection.

Morphometric aspects of the articular cartilage of rats treated with low-level laser therapy and exercise in a rheumatoid arthritis model

INTRODUCTION: Rheumatoid arthritis (RA) is classified as an autoimmune, chronic disease affecting diarthrodial joints and periarticular structures. OBJECTIVE: To evaluate whether low-intensity laser treatment (LLLT) and/or exercise reduce the deleterious effects of tissue in a rheumatoid arthritis model. METHODS: 128 rats were divided into two inflammatory periods: acute (7 days) and chronic (28 days) and subdivided into control, injury and treatment. The protocol with Freund's Complete Adjuvant was used in two inoculations, one intradermal and one intraarticular in the tibiofemoral joint, the control animals received saline solution. For treatment, LLLT 660 nm, 5 J/cm² was used in the sensitized joint and climbing exercise in stairways with an overload of 100 grams. After the experimental period, the animals were euthanized and the joints were prepared for morphometric analysis of the total thickness, superficial, deep, and cellular density of the articular cartilage. Generalized Linear Models with Sidak post-test were chosen. RESULTS: The control group was found to be different from the lesion group with greater joint cartilage thickness, andthe animals treated with exercise alone increased the joint cartilage compared to thecontrol group. CONCLUSION: The animals treated with laser association and exercise showed improvement in the morphometric aspects of the articular cartilage.

Benefícios da condroitinase abc associada a células-tronco mesenquimais na lesão espinhal aguda em ratos / Benefits of chondroitinase abc associated with mesenchymal stem cells in acute spinal cord injury in rats

Com o objetivo de estudar o efeito da condroitinase associada às células-tronco mesenquimais na lesão aguda da medula espinhal, utilizaram-se 50 ratos Lewis, distribuídos igualmente nos grupos: controle negativo (CN), tratamento com placebo (PLA), condroitinase (CDN), células-tronco mesenquimais (CTM) e condroitinase mais células-tronco mesenquimais (CDN+CTM). Todos os animais tiveram a medula espinhal exposta por laminectomia, e os grupos PLA, CDT, CTM e CDT+CTM sofreram também trauma medular compressivo. Após sete dias, procedeu-se à reexposição da medula espinhal, quando os grupos PLA e CTM receberam 4µL de líquido cefalorraquidiano artificial via intralesional, e os grupos CDT e CDT+CTM receberam o mesmo líquido contendo 2,2U de condroitinase. Após 14 dias da cirurgia inicial, todos os animais receberam 0,2mL de PBS via endovenosa, contudo, nos grupos CTM e CDT+CTM, esse líquido continha 1x106 CTM. Avaliou-se a capacidade motora até o 28o dia pós-trauma e, posteriormente, as medulas espinhais foram analisadas por RT-PCR, para quantificação da expressão gênica para BDNF, NT-3, VEGF, KDR e PECAM-1, e por imunoistoquímica, para detecção das células-tronco GFP injetadas (anti-GFP), quantificação dos neurônios (anti-NeuN) e da GFAP e vimentina, para avaliação da cicatriz glial. As análises estatísticas foram realizadas com o auxílio do Prism 5 for Windows, com o nível de significância de 5%. Não houve diferença entre os grupos quanto à capacidade motora. O grupo CDT+CTM apresentou maior imunoexpressão de neurônios viáveis do que o placebo. No CTM, houve maior expressão dos fatores neurotróficos BDNF e VEGF. E no CDT, houve menor imunoexpressão de vimentina. Concluiu-se que a associação CDT+CTM favorece a viabilidade neuronal após o trauma, que o tratamento com CTM promove aumento na expressão dos fatores tróficos BDNF e VEGF e que o tratamento com condroitinase é efetivo na redução da cicatriz glial.(AU)

The aim of this work was to study the effect of chondroitinase associated with mesenchymal stem cells in acute spinal cord injury. Therefore, 50 Lewis rats were distributed in the following groups: negative control (NC), treatment with placebo (PLA), chondroitinase (CDT), mesenchymal stem cells (MSC), and chondroitinase associated with mesenchymal stem cells (CDT + MSC). All animals had their spinal cord exposed by laminectomy, and the groups named PLA, CDT, MSC and CDT + MSC also suffered compressive spinal cord trauma. After seven days, the spinal cord was re-exposed, when the PLA and MSCs groups received 4uL of artificial cerebrospinal fluid through the lesion, and the CDT group and CDT + MSC received the same fluid containing 2,2U of chondroitinase. 14 days after the first surgery, all animals received 0.2ml of PBS intravenously; however, the MSC and CDT + MSC groups received the same liquid also containing 1x106 MSCs. The motor skills were evaluated up to 28 days post-injury and, subsequently, the spinal cords were analyzed by RT-PCR for BDNF, NT-3, VEGF, PECAM-1 and KDR gene expression quantification, immunohistochemistry to detect injected stem cells GFP (anti-GFP), to quantify neurons (anti-NeuN), GFAP and detect vimentin in order to evaluate the glial scar. Statistical analyzes were performed by Prism 5 for Windows using a 5% level of significance. There was no difference between groups with regarding motor capacity. The CDT + MSC group showed increased immunoreactivity of viable neurons than placebo. In MSC, there was a greater expression of neurotrophic factors BDNF and VEGF. Also, there was less vimentin immunostaining in group CDT. It was concluded that CDT + MSC association promotes neuronal viability after trauma, in which treatment with MSC promotes increased expression of BDNF and VEGF trophic factors, and also that treatment with chondroitinase is effective in reducing the glial scar.(AU)

Morphometric analysis of rat femoral vessels under a video magnification system / Análise morfométrica dos vasos femorais de ratos sob magnificação por sistema de vídeo

The right femoral vessels of 80 rats were identified and dissected. External lengths and diameters of femoral arteries and femoral veins were measured using either a microscope or a video magnification system. Findings were correlated to animals' weights. Mean length was 14.33 mm for both femoral arteries and femoral veins, mean diameter of arteries was 0.65 mm and diameter of veins was 0.81 mm. In our sample, rats' body weights were only correlated with the diameter of their femoral veins

Os vasos femorais de 80 ratos foram identificados e dissecados. O comprimento e o diâmetro externo da artéria e da veia femoral foram mensurados com o auxílio de um microscópio e um sistema de magnificação por vídeo. Esses parâmetros foram correlacionados com o peso do animal. O comprimento de ambos os vasos femorais foi de 14,33 mm, e a média do diâmetro das artérias foi de 0,65 mm, e das veias, de 0,81 mm. Na nossa amostra, o peso dos animais se correlacionou apenas com o diâmetro da veia femoral

Contribuição da aplicação do ultrassom de baixa potência na prevenção de osteopenia em tíbias de ratos sob ausência de carga / The contribution of the application of low power ultrasound to the prevention of rat tibial osteopenia under the absence of load

Este trabalho objetivou verificar se o ultrassom de baixa potência (US) previne a ocorrência de osteopenia em tíbias de ratos sob ausência de carga. Foram utilizados 45 Rattus novergicus albinus, Wistar adultos, machos, distribuídos em cinco grupos iguais: C - animais-controle livres em gaiolas por 21 dias; S - animais suspensos pela cauda por 21 dias; ST - suspensos pela cauda por 21 dias e concomitantemente tratados com US; S→C - suspensos por 21 dias e depois permanecendo livres em gaiolas por mais 21 dias; S→CT - suspensos por 21 dias e depois permanecendo livres em gaiolas por mais 21 dias e concomitantemente tratados com US. O tratamento foi realizado com US de 1,5MHz, ciclo de trabalho 1:4, 30mW/cm², na tíbia direita, por 15 sessões de 20 minutos cada, cinco sessões por semana. Ainda vivos, os animais foram submetidos a exame de densitometria óssea para verificação da densidade mineral óssea (DMO) e do conteúdo mineral ósseo (CMO). Após a eutanásia dos animais, as tíbias foram desarticuladas, dissecadas e submetidas a ensaio mecânico destrutivo para análise da força máxima (Fmáx) e da rigidez (R). Foram avaliados também o comprimento (L) e o diâmetro (D) no ponto médio da tíbia. O grupo S apresentou valores de DMO, CMO, Fmáx, R, L e D menores em relação ao grupo C, demonstrando que a suspensão pela cauda é prejudicial a estas variáveis. O tratamento dos animais suspensos com o US, grupo ST, elevou os valores de CMO e DMO em relação aos do grupo S, igualando-os aos do grupo C...

This work intended to verify if the low power ultrasound (US) prevents the occurrence of osteopenia on the tibia of rats under the absence of load. 45 adult male Wistar Rattus novergicus albinus were used, separated in five equal groups: C - control free animals in cages for 21 days; S - animals suspended by the tail for 21 days; ST - animals suspended by the tail for 21 days and concurrently treated with US; S→C - animals suspended for 21 days and then free in cages for another 21 days; S→CT - animals suspended for 21 days and then free in cages for another 21 days and concurrently treated with US. The treatment was performed with US with 1.5 MHz, work cycle 1:4, 30 mW/cm², on tibia, for 15 sessions of 20 minutes each, 5 sessions per week. While still alive, the animals underwent bone densitometry examination to verify the Bone Mineral Density (BMD) and the Bone Mineral Content (BMC). After the euthanasia of the animals, the tibias were disjointed, dissected and underwent destructive mechanical testing for the analysis of the maximum force (Fmax) and Rigidity (R). The length (L) and the diameter (D) of the middle point of the tibia were also measured. In group S, BMD, BMC, Fmax, R, L and D were smaller than in group C, demonstrating that the suspension by the tail is detrimental to these variables. The treatment of the suspended animals with the US, in group ST, increased the BMD and BMC compared to group S, leveling them to group C...

Retalho autólogo de grande omento como estrutura cirúrgica de reparo extraperitoneal. Estudo experimental comparativo, pareado e controlado de suas propriedades adaptativas / The autologous greater omental flap as a structure for extraperitoneal surgical repair: a comparative, paired, and controlled experimental study of its adaptive properties

Introdução: O grande omento vem sendo utilizado como estrutura de reparo desde o século XIX e a partir do século XX tem sido descrito, em meio extraperitoneal, para o tratamento de diversas afecções em várias especialidades cirúrgicas. Apesar de amplamente estudado a partir da década de 1960, não há descrição de estudos comparativos sobre o seu retalho em meio extra peritoneal. O objetivo do presente estudo foi analisar as características adaptativas do grande omento em meio extra peritoneal para identificar a real aplicabilidade cirúrgica desta estrutura. Métodos: Estudo experimental comparativo, pareado e controlado de 20 amostras teciduais de ratos (Rattus norvegicus) fêmeas obesas, irmãs da linhagem Sprague- Dawley. De cada animal foram analisados e comparados, macroscopicamente e microscopicamente, através das técnicas de Hematoxilina-eosina (HE) amostras de: (1) omento sem manipulação, (2) omento manipulado intraperitoneal, (3) omento manipulado extraperitoneal e (4) tecido adiposo subcutâneo. Resultados: omento extraperitoneal, macroscopicamente, apresentou uma coloração amarelado mais intenso, semelhante à gordura subcutânea adjacente, com alto grau de contração se comparado ao omento intraperitoneal de controle. Pela técnica de HE, foi identificado alto grau de fibrose e tamanho médio dos adipócitos semelhante ao omento de controle e inferior ao do subcutâneo (p<0,001). Conclusão: O omento extraperitoneal não se mostra capaz de promover regeneração tecidual, uma vez que não foi observado metaplasia à histologia do retalho translocado. Entretanto, pode servir para a correção de pequenas deformidades, para o tratamento de áreas isquêmicas, como estrutura carreadora para a reconstrução cirúrgica e como plataforma germinadora para o desenvolvimento de novos órgãos.

Introduction: The greater omentum was initially used in the repair of gastrointestinal defects in the 19th century; during the 20th century, it has been used extraperitoneally in the treatment of various disorders, in several surgical specialties. Despite the fact that the greater omentum was studies in detail in the 1960s, there are no reported comparative studies concerning the use of omental flaps extraperitoneally. The present study analyzed the adaptive features of the greater omentum in the extraperitoneal space, with the aim of identifying its surgical applicability. Methods: A paired, controlled comparative study was conducted using 20 tissue samples from 5 obese female Sprague-Dawley rats (Rattus norvegicus). The following specimens from each animal were analyzed and compared, macroscopically and microscopically, using the hematoxylin-eosin (HE) technique: (1) omentum without manipulation; (2) intraperitoneally manipulated omentum; (3) extraperitoneally manipulated omentum; and (4) subcutaneous adipose tissue. Results: Macroscopically, the extraperitoneal omentum exhibited a more intense yellowish color and a higher degree of contraction than the control (intraperitoneal) omentum. The extraperitoneal omentum was similar in color to the adjacent subcutaneous adipose tissue. HE staining revealed a high degree of fibrosis and an average adipocyte size, similar to that in the control omentum, but lower than that in subcutaneous adipose tissue (p< 0.001). Conclusion: The results of this study indicate that the extraperitoneal omentum was not able to promote tissue regeneration, as metaplasia of the translocated flap was not observed in the histological analysis. However, this structure may be used to correct small deformities, in the treatment of ischemic areas, as a carrier structure for surgical reconstruction and as a germination platform for the development of new organs.

Estudo do potencial desregulador endócrino do lodo de esgoto tratado (LETE) em ratos Wistar macho / Potential endocrine disruption of an urban sewage sludge (SS)sample evaluated in male Wistar rats

O processamento do esgoto urbano pelas estações de tratamento (ETE) produz uma mistura pastosa e complexa constituída por material orgânico (microorganismos, vegetais, etc.) e inorgânico (hidrocarbonetos aromáticos, minerais, metais pesados, etc.). Diante da possibilidade de utilização deste lodo para enriquecimento de solo agrícola (USEPA, 1999), o presente estudo teve como objetivo avaliar o potencial de desregulação endócrina do Lodo de uma Estação de Tratamento de Esgoto (LETE) do estado de São Paulo em modelos in vivo utilizando ratos machos adultos e recém-desmamados. No Estudo A, ratos Wistar machos com 98 dias de idade receberam por oito semanas ração basal (grupo GI) ou acrescida de 2.500, 5.000, 10.000 e 20.000ppm de LETE (grupos GII, GIII, GIV e GV respectivamente). Foram avaliados peso e aspectos histológicos do fígado, rins, adrenais, testículos, epidídimos, próstata ventral e vesículas seminais. Outros parâmetros analisados foram os níveis plasmáticos de hormônios sexuais e a qualidade e quantidade de espermatozoides. A exposição ao LETE reduziu a concentração plasmática do FSH e também o número de espermatozoides com movimento progressivo em ratos adultos. Esse resultado ocorreu de forma dose-resposta e significativamente nas concentrações de 10.000 e 20.000 ppm de LETE, podendo indicar comprometimento da qualidade do esperma. O Estudo B baseou-se no protocolo de Hershberger (OECD Nº 144, 2009) e visou avaliar efeitos androgénicos e anti-androgênicos em ratos Wistar machos desmamados no 21º dia pós-natal. Também nesses animais não foram registradas alterações do peso corpóreo e dos órgãos, do consumo de ração...

The complex mixture of organic and inorganic materials that constitutes sewage sludge (SS) has been proposed for use in agriculture and as raw material for the pottery industry. This study aimed to assess the potential for endocrine disruption of SS in vivo using adult and weanling male Wistar rats. In a first experiment, pubertal male rats (42th postnatal day, PND) were exposed ad libitum up to adulthood (56th PND) to a diet containing 0, 2,500, 5,000, 10,000 or 20,000 ppm of SS. The liver, kidneys, adrenals, testes, epididymis, ventral prostate and full seminal vesicle weights were evaluated, in addition to sexual hormones levels, sperm counts and sperm motility. In the second study, androgenic and antiandrogenic effects were evaluated in wealing male rats (21th PND), daily treated during 10 days with flutamide (anti-androgenic positive control, 3mg/kg/day, gavage), testosterone propionate (androgenic positive control, 1mg/kg/day, s.c.) and fed diets with SS at 10,000 or 20,000 ppm. In these later animals, no alterations were registered in body and organs weights, diet consumption and sperm countings. Exposure to the SS only induced a dose response decrease in the quality of adult rats sperm (first experiment), documented by decreased number of sperm with progressive movement (10,000 ppm, 20,000ppm)...

4NQO carcinogenesis: a model of oral squamous cell carcinoma / Carcinogenesis inducida por 4NQO: un modelo de carcinoma oral de células escamosas

The experimental oral carcinogenesis induced by the chemical 4-nitroquinoline 1-oxide (4NQO) is one of the most frequent in the study of squamous cell carcinoma of the oral cavity (CCEC). The clear advantage is that the model is very similar to the physiological process of malignancy. The model has clear benefits by and is suitable for applications in therapeutic research.

La carcinogénesis oral experimental inducida por el químico 4-nitroquinolina 1-óxido (4NQO) es uno de los métodos más frecuentes en el estudio del carcinoma de células escamosas de la cavidad oral (CCECO). La clara ventaja del modelo radica en el gran parecido al proceso fisiológico de la neoplasia maligna. El modelo tiene beneficios claros y es adecuado para las aplicaciones de la investigación terapéutica.

Effect of season on the reproductive organs of the female African giant rat (Cricetomys gambianus) in Zaria, Nigeria / Efecto estacional en los órganos reproductores de la rata gigante Africana (Cricetomys gambianus) hembra en Zaria, Nigeria

The study was carried out to determine the effect of season on the female reproductive organs of the African Giant rat using the standard methods, with the aim of obtaining the base-line values. The weights of the oviduct/uterus, vagina and the entire tubular organ were consistently higher during the harmattan season (0.789 +/- 0.07 g, 2.708 +/- 0.19 g and 3.455 +/- 0.25 g, respectively) than the hot ­ dry (0.591 +/- 0.02 g, 2.239 +/- 0.13 g and 2.831 +/- 0.14 g, respectively) and the rainy season (0.723 +/- 0.04 g, 2.412 +/- 0.01 g and 3.148 +/- 0.12 g, respectively). The mean weight and length of the ovary were not significantly different throughout the season, suggesting that the AGR may breed throughout the year. The slight increase in the weight of the tubular organ during the harmattan (November ­ February) and the rainy (June ­ October) season suggests that the seasons may be favourable for breeding, probably because of the abundance of food available to the rodents in the wild during the seasons. The decrease in weights of the organs during the hot-dry season (March ­ May) was, apparently, due to the unfavourable climatic conditions and food scarcity during the season. In conclusion, the results of the present study provide base -line morphometric data on the female reproductive organs of the AGR across the seasons.

Este estudio se llevó a cabo para determinar el efecto de las estaciones en los órganos reproductores femeninos de la rata gigante Africana mediante los métodos estándar, con el objetivo de obtener los valores basales. El peso del oviducto/útero, vagina y el órgano tubular completo fueron consistentemente más altos durante harmattan (la estación seca en Nigeria) (0,789 +/- 0,07 g, 2,708 +/- 0,19g y 3,455 +/- 0,25, respectivamente) que la estación seca-calurosa (0,591 +/- 0,02 g, 2.239 +/- 0,13g y 2.831 +/- 0,14, respectivamente) y la estación de lluvias (0,723 +/- 0,04 g, 2,412 +/- 0,01 y 3,148 +/- 0,12 g, respectivamente). La media de peso y longitud del ovario no fueron significativamente diferentes a lo largo de las estaciones, lo que sugiere que la rata gigante africana puede reproducirse durante todo el año. El ligero aumento en el peso del órgano tubular en las estaciones de harmattan (noviembre - febrero) y de lluvias (junio-octubre), sugiere que las estaciones pueden ser favorables para la reproducción, probablemente debido a la abundancia de alimentos disponibles para los roedores silvestres durante estas temporadas. La disminución en el peso de los órganos durante la estación cálida y seca (marzo - mayo) fue, al parecer, debido a las desfavorables condiciones climáticas y la escasez de alimentos durante la estación. En conclusión, los resultados de este estudio proporcionan una línea base de datos morfométricos para los órganos reproductores de la rata gigante africana hembra a través de las estaciones.

Influence of sildenafil and buflomedil on survival of randomized flaps in rats: an experimental study / Influência do buflomedil e do sildenafil na sobrevivência de retalhos randomizados em ratos: estudo experimental

BACKGROUND: Microcirculation dysfunction, as a consequence of localized vascular insufficiency, is considered to be one of the dominant causes of surgical flap necrosis. Several vasoactive drugs have been tested for the pharmacological treatment of tissue ischemia, with varying degrees of success. This study aimed to assess the impact of buflomedil and sildenafil on the viability of random skin flaps in rats. METHODS: Caudally pedicled skin flaps (10 x 3 cm) were created on the backs of rats. The animals were randomly assigned, in groups of 10, to three treatment groups: one group served as the vehicle control group, one group received buflomedil (10 mg/kg/d, orally), and a third group received the same dosage of sildenafil. Following seven days of dosing, the animals were sacrificed, and the viable flap area was determined. RESULTS: The average viable flap area for each group was: 16.2 ± 3.56 cm² (control group), 17.69 ± 2.54 cm² (buflomedil group), and 18.28 ± 3.74 cm² (sildenafil group). Data analysis by the Kruskal-Wallis test failed to show a statistically significant difference between the three groups. CONCLUSIONS: Neither buflomedil nor sildenafil showed a reduction in the necrotic area of random skin flaps in rats.

INTRODUÇÃO: A insuficiência no aporte sanguíneo e a consequente disfunção gerada no fluxo da microcirculação são consideradas causas dominantes de sofrimento de um retalho cirúrgico. Várias drogas vasoativas têm sido testadas para o tratamento farmacológico da isquemia tecidual, porém com graus variáveis de sucesso. Este estudo teve como objetivo avaliar a influência do buflomedil e do sildenafil na viabilidade de retalhos cutâneos ao acaso, em ratos. MÉTODO: Foram confeccionados retalhos cutâneos no dorso de ratos, com dimensões de 10 x 3 cm e base caudal. Foram utilizados 30 ratos, divididos em três grupos de 10 ratos cada: um grupo que recebeu apenas o veículo da solução (grupo controle); um grupo que recebeu buflomedil (grupo buflomedil); e um terceiro grupo que recebeu sildenafil (grupo sildenafil). A via de administração foi a oral e a dose foi de 10 mg/kg/dia para cada droga, durante sete dias. Ao final desse período, os animais foram sacrificados, sendo realizada a determinação das áreas viáveis dos retalhos. RESULTADOS: A média das áreas viáveis dos retalhos foi de 16,2 ± 3,56 cm² para o grupo controle, de 17,69 ± 2,54 cm² para o grupo buflomedil, e de 18,28 ± 3,74 cm² para o grupo sildenafil. A análise dos dados pelo teste de Kruskal-Wallis não demonstrou significância estatística entre os três grupos. CONCLUSÕES: A utilização do buflomedil e do sildenafil demonstrou não diminuir a área de necrose de retalhos randomizados em ratos.

Intramuscular 30 percent polymethylmethacrylate (PMMA) implants in a non-protein vehicle: an experimental study in rats / Implante intramuscular de polimetilmetacrilato (PMMA) 30 por cento, associado a veículo não-proteico: estudo experimental em ratos

INTRODUCTION: In the present study, the stability and biocompatibility of a 30 percent polymethylmethacrylate (PMMA) filling material implanted in the masseter muscle of rats were investigated according to the cytologic characteristics presented in the graft versus host reaction. METHODS: The study included 20 rats, which were divided into 4 groups: groups I, II, III, and IV corresponded to animals evaluated 7, 14, 45, and 60 days after surgery, respectively. The implant was placed in the right masseter muscle at the level of the mandibular angle. RESULTS: After 7 days, lymphoplasmacytic inflammatory infiltrates, a fibrous capsule, a large number of neutrophils, macrophages, and exudate were observed. The second group (14 days) showed granulation tissue composed of a lymphoplasmacytic inflammatory infiltrate, newly formed vessels, and a fibrous capsule. However, the second group also exhibited regeneration of the muscle fibers, and a decreased number of neutrophils and exudate. After 45 and 60 days, the inflammatory infiltrate decreased in intensity compared to the first 2 groups. CONCLUSIONS: The inflammatory reaction caused by PMMA is transient and does not compromise the function and the shape of the masseter muscle tissue, suggesting that PMMA is biocompatible.

INTRODUÇÃO: Este trabalho busca avaliar, em ratos, a estabilidade e a biocompatibilidade de um material de preenchimento à base de polimetilmetacrilato (PMMA) a 30 por cento implantado no músculo masseter, por meio do padrão, e a organização reacional no tecido receptor. MÉTODO: Foram utilizados 20 ratos, divididos em quatro grupos: grupo I, que correspondeu ao período de 7 dias de pós-operatório; grupo II, de 14 dias; grupo III, de 45 dias; e grupo IV, de 60 dias. O implante foi realizado no músculo masseter direito, na região do ângulo da mandíbula. RESULTADOS: No período de 7 dias, observou-se presença de infiltrado inflamatório linfoplasmocitário, com formação de cápsula fibrosa e presença de grande número de neutrófilos, macrófagos e formação de exsudatos. Em 14 dias, observou-se a formação de um tecido de granulação composto por infiltrado inflamatório linfoplasmocitário, vasos de neoformação e cápsula fibrosa. Porém, nesse tempo experimental, nota-se a regeneração das fibras musculares e a diminuição do número de neutrófilos e exsudatos. Após 45 dias e 60 dias, observou-se, no tecido muscular, diminuição da intensidade do infiltrado inflamatório, comparativamente aos tempos experimentais anteriores. CONCLUSÕES: A reação inflamatória provocada pelo PMMA é transitória e não compromete as funções e o contorno desse tecido muscular, o que sugere que o PMMA é biocompatível.

Microscopic anatomy of the lower respiratory system of the African giant pouched rat (Cricetomys gambianus, Waterhouse 1840) / Anatomía microscópica del sistema respiratorio inferior de la rata gigante Africana (Cricetomys gambianus, Waterhouse 1840)

A qualitative and quantitative study, by light microscopy, was undertaken on the lower respiratory system of the African Giant pouched rat. Specifically, the trachea, bronchi and lungs were stained with Haematoxylin and eosin, Alcian blue at a pH of 2.5 and Periodic Acid-Schiff stains. Three cell types were identified in saggital sections of the trachea: the ciliated cells, basal cells and mucous cells. Fibers of the trachealis muscles in the laminar propria separated the underlying cartilages from the basal cells. Mucous cells were visible only in the membranous portion of the trachea and they were predominant in the rostral and caudal portion of the trachea. Lobar bronchi consisted of cuboidal epithelium and a layer of one or two smooth muscle cells and opened into segmental bronchi and respiratory bronchiole. Some tracheal cartilaginous rims stained blue with AB while most glandular cells stained red with PAS. The diameter of respiratory bronchiole, alveoli duct and alveoli were 24.93 µm (+/- 1.27), 21.14 um (+/- 0.66) and 12.95 um (+/- 0.21), respectively. These and other findings were compared with similar report in other rodents.

Se realizó un estudio cualitativo y cuantitativo, mediante microscopía de luz, en el sistema respiratorio inferior de la rata gigante Africana. La tráquea, los bronquios y los pulmones fueron teñidos con hematoxilina y eosina, azul Alcián a pH de 2,5 y ácido periódico de Schiff. Tres tipos de células fueron identificadas en las secciones sagitales de la tráquea: células ciliadas, basales y mucosas. Las fibras del músculo traqueal en la propia laminar separados los cartílagos subyacente de las células basales. las células mucosas son visibles sólo en la porción membranosa de la tráquea y predominan en la parte rostral de la porción caudal de la tráquea. Los bronquios lobares consistían en epitelio cúbico y una capa de una o dos células de músculo liso y abierto en los bronquios y bronquiolos segmentarios respiratorias. Algunos bordes azules cartilaginoso traqueal manchada con AB, mientras que la mayoría de las células glandulares teñido de rojo con PAS. El diámetro de los bronquiolos respiratorios, conductos alveolares y los alvéolos fueron 24,93 m (+/- 1,27), 21,14 m (+/- 0,66) y 12,95 m (+/- 0,21), respectivamente. Estos y otros resultados se compararon con el informe similar en otros roedores.

A comparative histological study of the tongue of rat (Rattus norvegicus), bat (Eidolon helvum) and pangolin (Manis tricuspis) / Estudio histológico comparativo de la lengua de rata (Rattus norvegicus), murciélago (Eidolon helvum) y pangolín (Manis tricuspis)

This study assessed the micro anatomical differences in the tongue of rat, bat and pangolin with a view to establishing the functional anatomical differences of these mammalian tongues on their dietary pattern. Ten rats, ten bats and ten pangolins were used for this study. The animals were sacrificed and the tongue excised and processed for light microscopical study adopting the following stains: Haematoxylin Eosin, Verhoeff Gieson and Masson trichrome. The results showed non papillation of the keratinized stratified epithelium of pangolin tongue unlike the papillation seen in the tongue of the rat and bat. While the filiform papillation seen in the rat was bristle like, the filiform papillae in the bat were crown-like. There was also an unusual dense collagenous ring in the proximal portion of the pangolin tongue which was absent in other mammals. There were taste buds along the lateral walls of the vallate papillae in the distal portion of the tongue of rats and bats but none was found in the pangolins. In conclusion, the morphology of the tongues of these mammals showed a relationship between their feeding pattern and the adaptive changes in the microanatomy of their tongue.

Se evaluó los aspectos micro-anatómicos de la lengua de la rata, murciélago y pangolín, con miras a establecer las diferencias funcionales anatómicas de las lenguas de estos mamíferos en su patrón alimentario. Diez ejemplares de cada animal se utilizaron para este estudio. Los animales fueron sacrificados y las lenguas fueron extirpadas y procesadas para el estudio microscópico de luz, usándose las tinciones: Hematoxilina Eosina, Verhoeff Gieson y tricrómico de Masson. Los resultados mostraron la no papilación del epitelio estratificado queratinizado de la lengua de pangolines a diferencia de la papilación vista en la lengua de la rata y del murciélago. Por otro lado, las papilas filiformes vistas en la rata se presentaban como puntas, siendo como coronas en el murciélago. También hubo un inusual anillo de colágeno denso en la porción proximal de la lengua de pangolines, estando ausente en los otros mamíferos. Se observaron botones gustativos a lo largo de las paredes laterales de las papilas caliciformes en la porción distal de la lengua de las ratas y los murciélagos, pero ninguno fue encontrado en la de los pangolines. En conclusión, la morfología de las lenguas de estos mamíferos mostró una relación entre su patrón de alimentación y los cambios de adaptación en la anatomía microscópica de la lengua.

Altered kidney morphology and enzymes in streptozotocin induced diabetic rats / Morfología y enzimas renales alteradas en ratas con diabetes inducida por estreptozotocin

We studied the effects of streptozotocin (STZ)-induced diabetes on kidney morphology, anatomy, architecture and on the activities of aminotransferases (AST and ALT), alkaline phosphatase (ALP) and pseudocholinesterase (PChE) in albino rats. The aim of the study was to investigate the association between diabetic kidney complications and kidney enzyme alterations. This study was performed in the Department of Anatomy and Institute of Pharmaceutical Sciences, Baqai Medical University, Karachi and Pathology department of College of Physicians & Surgeons (CPSP) Pakistan in 2007-08. Diabetes was induced by a single dose of STZ (45 mg/kg, b.w.) given intraperitoneally in sodium citrate buffer at pH 4.5. Eighty (80) albino rats were divided into five groups: control (A) and STZ treated (B, C, D, and E) which were sacrificed 2, 4, 6 and 8 weeks post treatment respectively. Histopathology of kidney showed lesions similar to human glomerulosclerosis, glomerular membrane thickening, arteriolar hyalinization and tubular necrosis. Increased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and pseudocholinesterase (PChE) were observed in the kidney. It seems that the diabetic complications in the kidney are likely to be associated with alterations in enzyme levels.

Se estudiaron los efectos de la diabetes inducida por estreptozotocin (STZ) sobre la morfología, anatomía, arquitectura y sobre las actividades de aminotransferasas (ALT y AST), fosfatasa alcalina (ALP) y pseudocolinesterasa (PChE) en los riñones de ratas albinas. El objetivo del estudio fue investigar la asociación entre las complicaciones renales diabéticas y la alteración de las enzimas renales. Este estudio se realizó en el Departamento de Anatomía y el Instituto de Ciencias Farmacéuticas, Universidad de Medicina Baqai, Karachi y el departamento de Patología de Colegio de Médicos y Cirujanos (CPSP) Pakistán entre el 2007-2008. La diabetes fue inducida por una dosis única de STZ (45 mg / kg de peso corporal) administrada por vía intraperitoneal en tampón de citrato de sodio a pH 4.5. Ochenta (80) ratas albinas fueron divididas en cinco grupos: control (A) y STZ tratados (B, C, D y E), que se sacrificaron a las 2, 4, 6 y 8 semanas después del tratamiento, respectivamente. La histopatología del riñón mostró lesiones similares a la glomeruloesclerosis en humanos, engrosamiento de la membrana glomerular, hialinización arteriolar y necrosis tubular. Aumento de los niveles de aspartato aminotransferasa (AST), alanina aminotransferasa (ALT), fosfatasa alcalina (ALP) y pseudocolinesterasa (PChE) fueron observados en el riñón. Parece que las complicaciones de la diabetes en el riñón están directamente asociadas con alteraciones en los niveles de las enzimas.

Sexual dimorphism with respect to the macro-morphometric investigations of the forebrain and cerebellum of the grasscutter (Thryonomys swinderianus) / Dimorfismo sexual en relación con la investigación macro-morfométrica del cerebro y cerebelo del grasscutter (Thryonomys swinderianus)

This study was carried out to record the morphometric parameters of the brain of male and female grasscutters. Ten healthy grasscutters (5 males and 5 females) were used in this study. The mean brain weights were 9.80 + 0.50 g and 10.27 + 0.45 g for males and females respectively. The olfactory bulb mean weight was 0.57 + 0.05 g for males and 0.43 + 0.10 g for females. The cerebral and cerebellar mean lengths of 3.14 + 0.04 cm and 1.34 + 0.04 cm for males, 6.26 + 0.10 cm and 3.80 + 0.32 cm for females were observed. The cerebrum, cerebellum and olfactory bulb account for 70%, 12% and 6% of the total brain weight in males and 64%, 13% and 4% in the females respectively. The mean brain lengths were 5.63 + 0.07 cm and 6.26 + 0.1 cm for males and females respectively. There were significant differences in the body and olfactory bulb weights and also, in the whole brain and cerebral lengths between the males and females. In our present research, the ratios of 0.01 for males and 0.006 for females were observed. This suggests a relatively low brain weight in the ruminants. The olfactory bulb in the male is larger than that in the females. Females in turn have longer brain dimension than the males. Cerebellum has no sex variation both in weight and in length.

Este estudio se llevó a cabo para registrar los parámetros morfométricos del cerebro de grasscutters machos y hembras. Diez grasscutters sanos (5 machos y 5 hembras) fueron utilizados en este estudio. La media de peso del cerebro fueron 9,80 +/- 0,50 g y 10,27 +/- 0,45 g para los machos y hembras respectivamente. El peso medio del bulbo olfatorio fue 0,57 +/- 0,05 g para los machos y 0,43 +/- 0,10 g para las hembras. La longitud media del cerebro y del cerebelo fue de 3,14 +/- 0,04 y 1,34 cm +/- 0,04 cm para los machos, y 6,26 +/- 0,10 cm y 3,80 +/- 0,32 cm para las hembras, en las muestras observadas. El cerebro, cerebelo y el bulbo olfatorio representaron un 70%, 12% y el 6% del peso total del cerebro en machos y 64%, 13% y 4% en las hembras, respectivamente. La media de las longitudes del cerebro fueron 5,63 +/- 0,0 y 6,26 cm +/- 0,1 cm para los machos y hembras respectivamente. Hubo diferencias significativas en el peso del cuerpo y el bulbo olfatorio, y también en la longitud total del cerebro de machos y hembras. En nuestra actual investigación, los índices de 0,01 para los machos y de 0,006 para las hembras fueron observados. Esto sugiere un peso relativamente bajo en el cerebro de rumiantes. El bulbo olfatorio en los machos es mayor que en las hembras. A su vez, las hembras presentan una dimensión cerebral mayor que los machos. El cerebelo no tuvo variación según el sexo tanto en peso como en longitud.

Comparative craniometric study of fat sand rat [Psammomys obesus] and four toed jerboa [Allactaga tetradactyla] live in the similar habitats

The present study deals with the skull structure in two species of rodents, namely Psammomys obesus, the common name is Fat Sand rat, and Allactaga tetradactyla, the common name is four toed jerboa that lives in the same habitat. The skulls of Psammomys obesus and Allactaga tetradactyla are studied. The skull of Psammomys obesus, is triangular, strongly ridged and the sutures between its components are fairly apparent. It has two large parietals which are quadrate in shape. The frontal bone have triangular shape. The squamosal bone is triangular in shape. The zygomatic arch is slender and weak. The tympanic bullae are greatly expanded and the external auditory meatus is swollen. It has irregular shaped sphenoid bone consists of two unfused parts, presphenoid and basisphenoid. The occipital bone encloses the foramen magnum which is guarded laterally by two smooth articular occipital condyles. Exoccipital is broad. The mandible of Psammomys obesus consists of right and left halves firmly united in life at the mandibular symphysis. The body of the mandible can be divided into two parts, one bears the incisor teeth and the other contains the molar teeth. However, the cranium in Allactaga tetradactyla is broadly flattened in shape and the sutures between its component bones are apparent. It has two large parietals and the interparietal is narrow and triangular in shape. The frontal bones are flattened. On each side of the cranium, the squamosal which lies between the tympanic bullae and orbit. Supraoccipital is large, the zygomatic arch is slender, weak and consists of two parts, the zygomatic process of maxilla and zygomatic process of temporal. The nasal bones are elongated. The maxillary bone is irregular in shape. The tympanic bulla, exoccipital and paraoccipital process are short

Estereología comparativa entre el bazo del cuye (Cavia porcellus) y la rata (Rattus novergicus, Sprague Dawley) / Comparative stereology between the spleen of the Guinea pig (Cavia porcellus) and the rat (Rattus novergicus, Sprague Dawley)

El bazo es el órgano linfático periférico más grande del organismo y conocer sus aspectos morfológicos cuantitativos es importante para determinar posibles patologías. El objetivo del estudio fue determinar en dos especies: cuye (Cavia porcellus) y rata (Rattus novergicus Sprague Dawley), las características estereológicas del bazo, para obtener patrones de normalidad cuantitativos, los que servirán de base para futuros estudios morfofuncionales. Se utilizaron 5 bazos de cada especie, clínicamente sanos, obtenidos del Bioterio de la Universidad de La Frontera, Temuco, Chile. Los bazos fueron disecados y fijados en formalina tamponada al 10 por ciento y se determinó el volumen de éstos por el método de Scherle. Se obtuvieron 5 trozos por medio de Orientador los que fueron incluidos en paraplast. De cada trozo se obtuvieron 5 cortes histológicos de 3 micrones m de grosor y separados 200 micrones m entre sí, los cuales fueron teñidos con H-E. El porcentaje de pulpa roja, pulpa blanca y zona marginal en el bazo del cuye fue: 65,14 por ciento, 21,96 por ciento y 12,67 por ciento, respectivamente, y en la rata 53,9 por ciento de pulpa roja, 25,75 por ciento pulpa blanca y 15,87 por ciento de zona marginal. El número total de folículos fue 8,33 x 10² y 5,73x 10² para el cuye y la rata, respectivamente. Los resultados concuerdan con los obtenidos por otros autores, pudiéndose señalar un patrón cuantitativo del porcentaje de los compartimentos esplénicos de normalidad, que se podría considerar para futuros estudios morfo-funcionales.

The spleen is the largest peripheral lymphoid organ of the body so it is essential to know their morphological quantitative aspects in order to identify potential abnormalities. The aim of this study was to determine the parameters stereological spleen in normal two species commonly used in research such as the guinea pig and rat, to obtain quantitative patterns of normality, which will serve as a basis for future studies morphofunctional. 5 spleens were used for each species (Cavia porcellus and Rattus novergicus, Sprague Dawley) obtained from biotery the Universidad de La Frontera, Temuco, Chile. The spleens were dissected and fixed in formalin buffered to 10 percent and the volume is determined by the of Scherle method. 5 pieces were obtained through Orientator and these were included in paraplast. Each piece was performed histological cuts of 3 mm thick and separated 200 µm each other, which were stained with H-E. The percentage of redpulp, whitepulp and marginal zone in the Guinea pig was: 65.14 percent, 21.96 percent and 12.67 percent respectively, and in the rat 53.9 percent pulpred, 25.75 percent whitepulp and 15.87 percent of marginal zone. The total number of follicles was 8.33 x 10²follicles and 5.73 x 10² follicles for the Guinea pig and rat, respectively. The results are consistent with those obtained by other authors might identify a pattern of quantitative percentage of splenic compartments of normality that could be considered for future studies morpho-functional.

A Comparative Histomorphometric Study of the Stomach of Rat (Rattus norvegicus), Bat (Eidolon helvum) and Pangolin (Manis tricuspis) in Relation to Diet / Estudio Comparativo Histomorfométrico del Estómago de Rata (Rattus norvegicus), Murciélago (Eidolon helvum) y Pangolin (Manis tricuspis) en Relación con la Dieta

This study verified the comparative histomorphometric adaptations in the stomach of rat, bat and pangolin in relation to diet. Ten rats, ten bats and ten pangolins of both sexes were used for this investigation. The animals were sacrificed after slight anesthesia under chloroform inhalation. The stomach were excised, fixed in 10 percent formol saline and processed for light microscopic study. Stained slides were also subjected to morphometric analysis at a magnification of 400x. The results revealed that the cellular diameter/ density of parietal and zymogenic cells are significantly different in the three mammals (p<0.05) with the exception of the diameter of the zymogenic cells in pangolin which was not statistically significant (p>0.05) when compared with that of rat. Also, histological analysis revealed slight differences in the pattern of organization and distribution of connective tissue fibers. All these observations were reflections of the different pattern the stomachs of the three mammals have adopted to cope with their respective diets.

En este estudio se verificaron las adaptaciones histomorfométricas comparativas en el estómago de ratas, murciélagos y pangolines en relación a la dieta. Se utilizaron para esta investigación 10 ejemplares de cada especie, de ambos sexos. Los animales fueron sacrificados después de anestesia bajo inhalación de cloroformo. Los estómagos fueron extirpados, fijados en formol al 10 por ciento de solución salina y procesados para su estudio microscópico de luz. Los cortes teñidos fueron también objeto de análisis morfométrico con un aumento de X 400. Los resultados revelaron que el diámetro/densidad celular de parietal y las células cimógenas son significativamente diferentes en los tres mamíferos (p <0,05), con la excepción del diámetro de la células cimógenas de pangolines que no era estadísticamente significativa (p> 0,05) en comparación con la de rata. Por otra parte, el análisis histológico reveló ligeras diferencias en las características de organización y distribución de las fibras del tejido conjuntivo. Todas estas observaciones son un reflejo del patrón de los diferentes estómagos de los tres mamíferos, que han adoptado para hacer frente a sus respectivas dietas.

A comparative study of the ileum in rat (Rattus norvegicus), Bat (Eidolon helvum) and Pangolin (Manis tricuspis) as investigated using histological method / Estudio comparativo del íleon en rata (Rattus norvegicus), murciélago (Eidolon helvum) y pangolín (Manis tricuspis) utilizando como investigación el método histológico

The histological and morphometric differences in some parts of the gastrointestinal tracts of rat, bat and pangolin have been well established. This investigation aims at comparatively elucidating any adaptational changes the ileum of the three mammals must have adopted to meet its dietary requirements and also cope with their morphological differences. The investigation was carried out using ten rats, ten bats and ten pangolins of both sexes. The animals were slightly anaesthetized under chloroform inhalation. The intestines were harvested and the ileum excised and fixed in 10 percent formol saline. The tissues were processed for light microscopic study. The following stains were employed: Haematoxylin and eosin (H & E), Van Gieson and Verhoeff's haematoxylin elastic tissue stain. Stained slides were also analysed morphometrically. The results revealed microstructural modifications which characterized the mucosa as well as the pattern of distribution of the conjuntive tissue fibers in the ileum of the three mammals. These modifications are means of successfully coping with their respective diets and morphological differences.

Las diferencias histológicas y morfométricas en algunas partes del tubo digestivo de ratas, murciélagos y pangolines han sido bien establecidos. Esta investigación tiene por objeto aclarar comparativamente cualquier cambio de adaptación del íleon de los tres mamíferos que hayan adoptado para satisfacer sus necesidades dietéticas y también hacer frente a sus diferencias morfológicas. La investigación se llevó a cabo usando 10 ratas, 10 murciélagos y 10 pangolines, de ambos sexos. Los animales fueron ligeramente anestesiados bajo inhalación de cloroformo. Los intestinos fueron expuestos, el íleon extirpado y fijado en formol salino al 10 por ciento. Los tejidos fueron procesados para su estudio por microscopía de luz. Los siguientes tinciones fueron empleadas: Hematoxilina y eosina (H & E), Van Gieson y tinción de hematoxilina para tejidos elásticos de Verhoeff. Los cortes teñidos también se analizaron morfométricamente. Los resultados revelaron modificaciones microestructurales características de la mucosa, así como el patrón de distribución de las fibras de tejido conjuntivo en el íleon de los tres mamíferos. Estas modificaciones son el medio para entender sus diferencias en la dieta y morfología respectivamente.

Ultrastructure of the myelinated and unmyelinated nerve fibers of the tongue mucosa of albinus rat (Wistar) with aging / Ultraestructura de las Fibras Nerviosas Mielínicas y Amielínicas de la Mucosa Lingual de ratas Albinas (Wistar) Envejecidas

El objetivo de esta investigación fue estudiar las fibras sensitivas mielinizadas y amielínicas localizadas en la lámina propia subepitelial de la mucosa lingual de ratas. Se usó el método de impregnación argéntica, microscopía MET y mediciones morfométricas. Los resultados revelaron que los fascículos de fibras subepiteliales de las regiones anterior, media y posterior de la lengua provenían de su capa muscular profunda. Los grupos de fibras fueron localizados dentro del tejido conectivo de la lámina propia. Estas fibras nerviosas se ramificaron varias veces y en el tejido conectivo de las papilas formaron terminaciones simples o ramificados. Las papilas fungiformes y valadas contenían numerosas terminaciones nerviosas. La ultraestructura demostró en el axoplasma la presencia de neurofilamentos, mitocondrias y microtúbulos; aunque los registros morfométricos de las fibras mielinizadas mostraron que alrededor del 44 por ciento tenían un diámetro entre 3 y 4 µm, el valor promedio fue de 4.5 µm. El diámetro mayor fue de 12 µm y el menor de 1.4 um. Los rangos de menores diámetros fueron de 1 a 3 µm, siendo el promedio de 2.33 µm. En relación al espesor de las vainas de mielina, los valores obtenidos fueron de 0.2 a 0.8 um siendo el valor promedio de alrededor de 0,5 µm, en el 90 por ciento de ellas. En las fibras amielínicas los mayores diámetros (62 por ciento) variaron entre 0.25 y 0.75 µm. El valor promedio fue de 0.6 µm, siendo el valor máximo 3.17 µm y el mínimo 0.2 µm. El menor diámetro fue obtenido en 44 por ciento de las fibras amielínicas y los rangos variaron entre 0.2 y 0.4 µm. El valor máximo obtenido fue de 1 µm y el mínimo 0.12 µm.

The purpose of this paper was to study the sensory myelinated and unmyelinated nerve fibers found in the subepithelial lamina propria of tongue mucosa of aging rats. It was used the silver impregnation, transmission electron microscopy methods and morphometric measurements. The results revealed that subepithelial nerve fiber bundles of the anterior, medium and posterior regions of tongue were arise from deep muscular layer of tongue. The nerve fiber bundles were verified inside of the connective tissue of lamina propria. These nerve fibers branched several times and into the connective tissue papillae they form a single or ramified sensory nerve endings. The fungiform and vallate papillae contain numerous nerve terminals. The fine structure demonstrated that in the axoplasm were noted the presence of neurofilaments, mitochondria and microtubules. Although the morphometric data of myelinated fibers showed that about 44% having larger diameter between 3 to 4 µm and the mean value was 4.5 µm. The largest diameter was 12 µm and the smaller was 1.4 um. The smallest diameter ranges from 1 to 3 µm, being that the mean value was 2.33 µm. Concerning to the thickness of myelin sheets were revealed the values ranging from 0.2 to 0.8 µm being that the 90% present the values around 0.5 µm. The unmyelinated fibers showed the largest diameter (62%) varying from 0.25 to 0.75 µm. The mean value was 0.6 µm being the maximum value was 3.17 µm and the minimum was 0.2 µm. The smallest diameter was obtained in 44% of unmyelinated fibers which the diameter ranges from 0.2 to 0.4 µm.Then maximum value obtained was 1 µm and the minimum was 0.12 µm.