Rhinosinusal polyposis and inverted papilloma: a morphometric comparative study

Introduction Nasal obstruction is one of the main rhinologic complaints, and two diseases must be investigated as differential diagnosis: rhinosinusal polyposis and inverted papilloma. Using traditionalmethods, the differential diagnosis between these diseases may be difficult. The morphometric study may be a useful tool for differential diagnosis and to define prognosis. Objective Calculate the morphometric values of rhinosinusal polyposis and inverted papilloma and compare the average of variables obtained between the groups. Methods The nasal mucus of 10 patients who had surgery in the Department of Otorhinolaryngology and Surgery of Head and Neck was studied; 5 had rhinosinusal polyposis and 5 had inverted papilloma. After the capture and print of corresponding data of each slide, the largest and smallest diameters of the nuclei were measured and the morphometric variables were calculated: average diameter, perimeter, ratio between largest and smallest diameter, volume, area, ratio of volume to area, form coefficient, contour index, and eccentricity. Results We found a significant difference (p < 0.05) between the two groups in the following morphometric variables: largest diameter, smallest diameter, average diameter, volume, area, perimeter, and ratio of volume to area, indicating that these parameters can be useful in diagnostic differentiation between these diseases. Conclusion We founded morphometric variables higher in patients with inverted papilloma, which can be related to the neoplastic origin of the inverted papilloma. The analysis of nuclear parameters is an instrument of great value in the differential diagnosis between rhinosinusal polyposis and inverted papilloma.

Rhinosinusal Polyposis and Inverted Papilloma: A Morphometric Comparative Study.

Introduction Nasal obstruction is one of the main rhinologic complaints, and two diseases must be investigated as differential diagnosis: rhinosinusal polyposis and inverted papilloma. Using traditional methods, the differential diagnosis between these diseases may be difficult. The morphometric study may be a useful tool for differential diagnosis and to define prognosis. Objective Calculate the morphometric values of rhinosinusal polyposis and inverted papilloma and compare the average of variables obtained between the groups. Methods The nasal mucus of 10 patients who had surgery in the Department of Otorhinolaryngology and Surgery of Head and Neck was studied; 5 had rhinosinusal polyposis and 5 had inverted papilloma. After the capture and print of corresponding data of each slide, the largest and smallest diameters of the nuclei were measured and the morphometric variables were calculated: average diameter, perimeter, ratio between largest and smallest diameter, volume, area, ratio of volume to area, form coefficient, contour index, and eccentricity. Results We found a significant difference (p < 0.05) between the two groups in the following morphometric variables: largest diameter, smallest diameter, average diameter, volume, area, perimeter, and ratio of volume to area, indicating that these parameters can be useful in diagnostic differentiation between these diseases. Conclusion We founded morphometric variables higher in patients with inverted papilloma, which can be related to the neoplastic origin of the inverted papilloma. The analysis of nuclear parameters is an instrument of great value in the differential diagnosis between rhinosinusal polyposis and inverted papilloma.

Preoperative tranilast as adjunctive therapy to primary pterygium surgery with a 1-year follow-up.

PURPOSE: To determine the efficacy of tranilast as an adjunctive therapy in conjunctival autograft. METHODS: Twenty-nine patients were randomly allocated to the Tranilast Group (n=15) or the Control Group (n=14). The Tranilast Group received a subconjunctival injection of 0.5% tranilast 30 days prior to surgery. Conjunctival autograft was performed in both groups using fibrin sealant and 0.02% subconjunctival mitomycin C at the end of the surgery. After the resection of the pterygium, immunohistochemistry was performed with 100 cells to identify epithelial cells positive for transforming growth factor-ß (TGF-ß). Subjective symptoms were evaluated using a 5-point scale, and the recurrence rate was assessed. RESULTS: Both groups showed improvements in their symptoms and similar clinical results. Compared with the Control Group, the Tranilast Group failed to show a decreased recurrence rate (p=0.59). However, the number of epithelial cells expressing TGF-ß was lower in the Tranilast Group (5 cells; 95% CI: 2.56-13.15; Control Group, 16 cells, 95% CI: 11.53-24.76; p=0.01). Minimal but reversible complications, including glaucoma secondary to corticosteroids and granuloma, occurred during the study. CONCLUSION: Tranilast was effective in decreasing the number of pterygium epithelial cells expressing TGF-ß.

Preoperative tranilast as adjunctive therapy to primary pterygium surgery with a 1-year follow-up / Terapia auxiliar com o tranilast pré-operatório na cirurgia do pterígio primário com um ano de seguimento

Purpose: To determine the efficacy of tranilast as an adjunctive therapy in conjunctival autograft. Methods: Twenty-nine patients were randomly allocated to the Tranilast Group (n=15) or the Control Group (n=14). The Tranilast Group received a subconjunctival injection of 0.5% tranilast 30 days prior to surgery. Conjunctival autograft was performed in both groups using fibrin sealant and 0.02% subconjunctival mitomycin C at the end of the surgery. After the resection of the pterygium, immunohistochemistry was performed with 100 cells to identify epithelial cells positive for transforming growth factor-β (TGF-β). Subjective symptoms were evaluated using a 5-point scale, and the recurrence rate was assessed. Results: Both groups showed improvements in their symptoms and similar clinical results. Compared with the Control Group, the Tranilast Group failed to show a decreased recurrence rate (p=0.59). However, the number of epithelial cells expressing TGF-β was lower in the Tranilast Group (5 cells; 95% CI: 2.56-13.15; Control Group, 16 cells, 95% CI: 11.53-24.76; p=0.01). Minimal but reversible complications, including glaucoma secondary to corticosteroids and granuloma, occurred during the study. Conclusion: Tranilast was effective in decreasing the number of pterygium epithelial cells expressing TGF-β. .

Objetivo: Determinar a eficácia do tranilast, como terapia auxiliar no transplante autólogo de conjuntiva. Métodos: Vinte e nove pacientes foram randomizados em dois grupos: Grupo Tratado (15) e Grupo Controle (14). Trinta dias antes da cirurgia, o Grupo Tratado recebeu uma injeção subconjuntival de tranilast a 0,5%. O transplante autólogo de conjuntiva foi realizado em ambos os grupos, usando-se a cola de fibrina e a mitomicina 0,02% subconjuntival, ao final da cirurgia. Cada paciente foi examinado por 12 meses de acompanhamento. A imuno-histoquímica foi realizada, mediante um total de 100 células, a fim de que se contassem as células epiteliais positivas, para o fator de crescimento transformador beta (TGF-β), após a cirurgia do pterígio. Os sintomas subjetivos foram avaliados usando-se uma escala de cinco pontos, e a taxa de recorrência foi avaliada. Resultados: Os 2 grupos apresentaram melhora dos sintomas e com resultados clínicos similares. Quando comparado com o Grupo Controle, o Grupo Tratado falhou em mostrar uma diminuição da taxa de recorrência (p=0,59). Entretanto o número de células epiteliais expressando o TGF-β foi menor no Grupo Tratado (5 células; 95% CI=2,56-13,15; Grupo Controle, 16 células; 95% CI: 11,53-24,76, p=0,01). Complicações mínimas, mas reversíveis, ocorreram durante o estudo, incluindo glaucoma secundário ao uso de corticoide e granuloma. Conclusão: O tranilast foi efetivo em diminuir o número células epiteliais do pterígio expressando o TGF-β. .

Effect of statins and aerobic physical exercise on liver function in dyslipidemic rats: morphometric study / Efecto de las estatinas y ejercicio físico aeróbico sobre la función hepática en ratas dislipémicas: estudio morfométrico

The present study was carried out to evaluate the effect of statins associated with physical exercise (PE) in liver cells in dyslipidemic rats through cariometry. The animals were divided into six groups: animals subjected to a hypercholesterolemic diet (HD), simvastatin, with (G1) and without (G2) physical exercise (PE); HD submitted (G3) or not (G4) to PE, and commercial food diet (F) with (G5) and without (G6) PE. Histological analysis of the liver was performed by staining the slides with hematoxylin and eosin. The cariometric study included measuring the major and minor diameters of the hepatocytes nuclei. The Shapiro-Wilk test was also performed. To determine the differences among the groups, the Kruskal-Wallis Test with Dunn's post-test were conducted. The significance level was set at 5 percent. No difference was found in the hepatocytes nuclei between G5 and G6. When these groups were related with G3 and G4, reduced nuclei were observed. There was no difference between G1 and G6. The comparison between G6 and G2 showed that the nuclei in G2 were smaller. No difference was detected between G5 and G1. Changes were observed in the nuclei shape in G2 in comparison to G1. Considering G2 and G3, a decrease in the size of nuclei was observed in G3. On the other hand, G2 showed changes in shape in the comparative analysis with G4. The size and shape of G1 nuclei were larger than G3 as well as changes in shape were observed when compared to G4. G4 showed smaller nuclei than G3. Therefore, F, associated or not with the practice of PE, does not alter the size and shape of the hepatocytes nuclei; HD combined with sedentarism influences changes in the morphometric parameters of hepatocytes; and the association of simvastatin and PE seems to protect the hepatocytes nuclei with regard to HD.

El presente estudio se realizó con la finalidad de evaluar el efecto de las estatinas asociadas con el ejercicio físico (PE) en las células del hígado, en ratas con dislipidemia a través de cariometría. Los animales fueron divididos en seis grupos: animales sometidos a una dieta hipocolesterolemiante (HD), simvastatina, con (G1) y sin (G2) ejercicio físico (PE); HD enviado (G3) o no (G4) para educación física y dieta comercial (F) con (G5) y sin (G6) PE. El análisis histológico del hígado se realizó por tinción de los portaobjetos con hematoxilina y eosina. El estudio cariométrico incluyó la medición de los diámetros mayor y menor de los núcleos de hepatocitos. Se realizó la prueba de Shapiro-Wilk. Para determinar las diferencias entre los grupos, se realizó la prueba de Kruskal-Wallis con Dunn. El nivel de significación se fijó en 5 por ciento. No se encontraron diferencias en los núcleos de hepatocitos entre G5 y G6. Los núcleos fueron observados cuando estos grupos estaban relacionados con G3 y G4. No hubo diferencia entre G1 y G6. La comparación entre G6 y G2 mostró que los núcleos en G2 eran más pequeñas. No se detectaron diferencias entre el G5 y G1. Se observaron cambios en la forma núcleos en G2 en comparación con G1. Considerando G2 y G3, se observó en G3 una disminución en el tamaño de los núcleos. En el análisis comparativo con G4, G2 mostró cambios en la forma . El tamaño y forma de los núcleos G1 eran más grandes que G3, así como cambios en la forma se observaron cuando se compararó con G4. G4 mostraron núcleos menores que G3. Por tanto, F, asociados o no a la práctica de PE, no altera el tamaño y la forma de los núcleos de hepatocitos; HD combinada con influencias sedentarismo cambios en los parámetros morfométricos de los hepatocitos, y la asociación de simvastatina y PE parece proteger a los hepatocitos con respecto a la HD.

Estresse pós-privação de sono: análises morfométricas do fígado / Stress caused by sleep deprival: liver morphometric analysis

OBJETIVO: Avaliar o efeito da exposição ao estresse pós-privação de sono em características celulares e nucleares do fígado de ratos. MÉTODOS: 16 ratos (Wistar) machos adultos (200-260 g) foram mantidos em ciclo de luz controlado recebendo dieta com quantidades usuais de sal e livre acesso à água e alimento. Os animais foram divididos em dois grupos de oito animais (grupo experimental e grupo controle). Os animais permaneceram na mesma gaiola (dois de cada vez) durante sete dias e, após esse período, foram pesados e separados. O animal do grupo controle continuou na mesma gaiola e o animal do grupo experimental foi colocado em aparato de privação de sono. Após as 96 horas, os dois ratos foram pesados,anestesiados, sacrificados com dose excessiva de anestésico e os fígados foram retirados. RESULTADOS: Não há diferença significante entre o grupo experimental e grupo controle em relação ao peso, embora haja diminuição de peso no grupo experimental. Nas análises cariométricas, houve diferença significante em relação ao diâmetro menor (p=0,03) e volume (p=0,04) do núcleo dos hepatócitos do grupo experimental. Nas análises esteriológicas, houve diferença significante do grupo experimental no núcleo (maior, p=0,036), do citoplasma (menor p=0,009) e outras estruturas (maior p=0,008). CONCLUSÃO: O estresse parece contribuir para alteração na estrutura celular hepática.

OBJECTIVE: To evaluate the effect of stress induced by sleep deprivation on nuclear and cellular features of rat liver. METHODS: 16 adult male Wistar rats (200-260 g) in controlled light cycle received diet with customary salt quantity and free access to water and food. The animals were divided into two groups with 8 animals each (experimental group and control group). Animals stayed in the same box (two at a time) during seven days andafter that period they were weighted e separated. The control group animal continued in the same box and the experimental group animal were transferred to a sleep deprivation apparatus. After the 96 hours the animals were sacrificed by an excessive anesthetic dose; animals were weighted and their liver extracted. RESULTS: There was no significant difference between experimental and control group regarding weight, although therewas a decrease of weight on the experiment group. Karyotipical analysis showed significant smaller diameter (p=0.03) and volume (p=0.044) of hepatocyte nuclei in experimental group. Stereological analyses showed significant differences in experimental group for nucleus (larger, p=0.036), cytoplasm (smaller, p=0.009) and other structures (larger, p=0.008). CONCLUSION: Stress seems to contribute to alteration of hepatic cell structure.

Efeito do exercício físico e estatinas na função muscular em animais com dislipidemia / Effect of physical exercise and statins on the muscle function in animals with dyslipidemia

As estatinas são utilizadas no tratamento das dislipidemias, com grande tolerância; no entanto, vários efeitos colaterais podem surgir, destacando-se miopatia. A prática regular do exercício físico (EF) produz modificações favoráveis no perfil lipídico; entretanto, pode gerar lesões musculares. OBJETIVO: Avaliar o efeito da associação entre exercício físico e estatinas na função muscular, pela análise histológica, em modelo experimental animal com dislipidemia. MÉTODOS: Foram utilizados 80 ratos machos Wistar, distribuídos em oito grupos, incluindo animais submetidos à dieta hipercolesterolêmica (DH), sinvastatina com (G1) e sem (G2) EF; DH e fluvastatina, com (G3) e sem EF (G4); alimentados com ração comercial (RC) na presença (G5) e ausência de (G6) EF; DH submetidos (G7) ou não (G8) a EF. A DH foi administrada por 90 dias, as estatinas e prática de EF em esteira rolante por oito semanas. Os animais foram sacrificados, e o músculo sóleo retirado para análise histológica. Aplicaram-se os testes t de Student pareado e análise multivariada, com nível significante para p < 0,05. RESULTADOS: As principais alterações histológicas encontradas foram fibras de diferentes diâmetros, atróficas, em degeneração, splitting, edema, infiltrado inflamatório. Essas alterações foram observadas em 90% dos animais do grupo G1, 80% do G2, 70% do G3, 30% do G4, 40% do G5 e 30% do G7. Nos grupos G6 e G8 identificaram-se fibras musculares com morfologia preservada. CONCLUSÕES: Na avaliação histológica muscular, a associação entre fluvastatina, sinvastatina e exercício físico acarreta alterações morfológicas com predomínio no uso da sinvastatina, variando de grau leve a grave, no músculo sóleo de ratos, induzidos pelos inibidores da HMG-CoA redutase.

Statins are used in the treatment of dyslipidemias with great tolerance; however, several side effects can arise, mainly myopathies. Regular practice of physical exercises (PE) produces beneficial alteration in the lipid profile, but it can result in muscular lesions. OBJECTIVE: to evaluate the effect of the association between physical exercise and statins in the muscular function through histological analysis in an experimental animal model with dyslipidemia. METHODS: 80 male Wistar mice, distributed in 8 groups, namely: animals submitted to a hypercholesterolemic diet (HD), symvastatin with (G1) and without PE (G2) ; HD and fluvastatin with (G3) and without PE (G4); fed with commercial food (CR) in the presence (G5) and absence of PE (G6); HD submitted (G7) or not (G8) to PE were used. The HD was administered statins and PE practice on treadmill for 90 days for 8 weeks. The animals were sacrificed, and the soleus muscle was removed for histological analysis. Paired t-tests and multivariate analysis were applied with significance level of p<0.05. RESULTS: The most important histological alterations found were fibers with different diameters and atrophic, with degeneration, splitting, edema and inflammatory infiltrate. These alterations were observed in 90% of animals from G1; 80% from G2; 70% from G3; 30% from G4; 40% from G5 and 30% from G7. In the G6 and G8 groups muscular fibers with preserved morphology were identified. CONCLUSION: In the muscular histological evaluation, the association of fluvastatin, symvastatin and physical exercise results in morphological alterations with predominance with the use of simvastatin, varying from a light to a high level, in the soleus muscle of mice, induced by HMG-CoA reductase inhibitors.

Effects of sucralose ingestion on fetal and placental weights and umbilical-cord length: experimental study / Efectos de la ingestión de sucralosa sobre el peso fetal y placentario y la longitud del cordón umbilical: estudio experimental

Sucralose is a sweetener of general use in over three thousand products (beverages, foods and medical diets), with utilization currently permitted for the general population in more than 80 countries, including for women of reproductive age. There is little information on the safe use of sucralose, and experimental studies have suggested that the administration of some sweeteners, by diverse routes, retards not only fetal and placental development but also umbilical cord size. The present study aimed to estimate the fetal and placental weights and umbilical-cord length in fetuses from rat dams, after ingestion and non-ingestion of sucralose. In the treated group (5 dams), sucralose was administered (via gavage) at the dose of 30 mg/kg/day, from the 10th to 14th day of pregnancy. In the control group (5 dams), saline solution was administered, at the same dose and by the same route. On the 20th gestation day, both groups were sacrificed for weighing of the fetuses and placentas and measurement of umbilical-cord length. Mean values of fetal weight and umbilical-cord length of the treated group were significantly lower than controls (Mann-Whitney Test, p<0.001). Placental weight did not differ statistically between treated and control groups. It can be concluded from the present work that sucralose ingestion at 30 mg/kg/day, from days 10 to 14 of pregnancy, diminished fetal weight and umbilical-cord length, which suggests passage of sucralose through the placental membrane.

La sucralosa es un edulcorante de uso general en más de tres mil productos (bebidas, alimentos y dietas médicas), con permisos de utilización para la población general en más de 80 países, entre ellos mujeres en edad reproductiva. Hay poca información sobre el uso seguro de la sucralosa, y los estudios experimentales han sugerido que la administración de algunos edulcorantes, por diversas vías, no sólo retrasa el desarrollo del feto y la placenta, sino también el tamaño del cordón umbilical. Este estudio tuvo como objetivo estimar el peso fetal y placentario y la longitud del cordón umbilical de los fetos de ratas madres después de la ingestión y la no ingestión de sucralosa. En el grupo tratado (5 crías), la sucralosa se administró (a través de sonda) en una dosis de 30 mg/kg/día, desde el día 10 hasta 14 de la preñez. En el grupo control (5 crías), se administró solución salina, con la misma dosis y por la misma vía. En el día 20 de la gestación, ambos grupos fueron sacrificados, para determinar el peso de los fetos y de las placentas y la medición de la longitud del cordón umbilical. Los valores medios del peso fetal y la longitud del cordón umbilical en el grupo tratado fueron significativamente más bajos que los controles (U de Mann-Whitney, p <0,001). El peso de la placenta no difirió estadísticamente entre los grupos tratados y los controles. Se puede concluir de este trabajo que el consumo de sucralosa en 30 mg/kg/día, desde lel día 10 al 14 de la preñez, disminuye el peso fetal y la longitud del cordón umbilical, lo que sugiere el paso de la sucralosa través de la membrana placentaria.

Effect of sodium cyclamate on the rat fetal exocrine pancreas: a karyometric and stereological study / Efectos del ciclamato de sodio en el pancreas exocrino fetal de ratas: estudio cariométrico y estereológico

The cyclamate, a sweetner substance derived from N-cyclo-hexyl-sulfamic acid, is largely utilized as a non-caloric artificial edulcorant in foods and beverages as well as in the pharmaceutical industry. The objective of this study was to evaluate karyometric and stereological alterations in the rat fetal pancreas resulting from the intraperitoneal administration of sodium cyclamate. The exocrine pancreas of ten fetuses of rats were evaluated, five treated and five controls chosen at random, in which five rats that received from the 10th to 14th days of pregnancy an intraperitoneal daily injection of sodium cyclamate at 60 mg/Kg of body weight during 5 days. At the 20th day of gestation, the animals were removed and weighed, as were their placentas; the length of the umbilical cords also were measured. After the laboratory processing, semi-seriated 6mm cuts stained with haematoxyline and eosine were performed. In seven karyometric parameters (major, minor, and medium diameters, volume, area, perimeter, and volume-area ratio), the increase was statistically significant in the treated group when compared with control group. Stereological parameters showed in the treated group a significant increase in the cellular volume and a significant reduction in the numerical cellular density. These results showed that the sodium cyclamate in pregnant rats led to retardation of fetal development and hypertrophy in the exocrine pancreas of the rat fetuses.

El ciclamato, es una substancia derivada del ácido N-ciclo-hexil-sulfámico, bastante usada como edulcorante no calórico en los alimentos y bebidas, así como en la industria farmacéutica. El objetivo de este estudio fue evaluar las alteraciones cariométricas y estereológicos en páncreas fetal de rata tras la administración intraperitoneal de ciclamato de sodio. El páncreas exocrino de diez de los fetos de rata fueron evaluados, cinco tratados y cinco controles seleccionados al azar, en el que cinco ratas recibieron del día 10 al día 14 de preñez una inyección intraperitoneal diaria de ciclamato de sodio a 60 mg/Kg de peso corporal durante 5 días. En el día 20 de gestación, los animales fueron retirados y pesados, al igual que sus placentas. Asimismo, se midió la longitud de los cordones umbilicales. Después del procesamiento de laboratorio, cortes semi-seriados de 6µm, se tiñeron con hematoxilina-eosina. En siete parámetros cariométricos (diámetros mayor, menor y medio, volumen, área, perímetro y relación área/volumen). El aumento fue estadísticamente significativo en el grupo tratado comparado con el grupo control. Los parámetros estereológicos mostraron en el grupo tratado un aumento significativo del volumen celular y una reducción significativa en la densidad numérica celular. Estos resultados mostraron que el uso del ciclamato de sodio en las ratas preñadas causa retardo en el desarrollo fetal e hipertrofia en el páncreas exocrino de los fetos de rata.

Muscle response to the association of statin and physical exercise in rats / Respuestas musculares de la asociación de estatina y ejercicio físico aeróbico en ratas

Physical exercise and statins, which are recommended for the treatment of dyslipidemia, are independently associated to the occurrence of muscle injury. The objective is analyze the effect of aerobic exercise associated to the use of simvastatin on the morphology of the gastrocnemius muscle. Thirty Wistar rats were divided into six groups, two of which received a standard diet (1 sedentary and 1 exercised) and four (1 sedentary with medication, 1 sedentary without medication, 1 exercised with medication, 1 exercised without medication) received a hypercholesterolemic diet (standard diet with the addition of cholesterol and coconut oil). Simvastatin (20 mg/Kg) was administered five days a week for eight weeks, together with aerobic training on a treadmill (9.75 m/min) for 60 minutes a day. The gastrocnemius muscle was removed, sliced, stained with Hematoxylin-Eosin and submitted to a histochemical reaction to determine mitochondrial activity. The data were analyzed using a paired t-test, analysis of variance and Scheffé's post hoc test (p<0.05). Greater histological alterations were found in the medicated and exercised animals, with a greater frequency of occurrence as well. The histochemical analysis revealed that the medicated groups had fibers with more intensive mitochondrial activity alongside fibers with an absence of reaction. The morphometric analysis revealed no significant differences between groups. It is suggested that simvastatin is a medication that leads to the occurrence of muscle injury and its administration in association with physical activity may exacerbate these injuries. This finding may be related to cellular respiration.

El ejercicio físico y las estatinas, son intervenciones recomendadas para el tratamiento de la dislipidemia y están independientemente asociadas con la ocurrencia de lesiones musculares. El objetivo fue analizar el efecto del ejercicio aeróbico asociado al uso de la sinvastatina en la morfología del músculo gastrocnemio. 30 ratas macho Wistar fueron divididos en 6 grupos, de los cuales 2 recibieron ración padrón, sedentarios, ejercitados y 4 recibieron dieta con alto nivel de colesterol, sedentarios con y sin medicamento, ejercitados con y sin medicamentos. La dieta fue elaborada a partir de una dieta padrón aumentada de colesterol y aceite de coco. La Sinvastatina (20 mg) fue administrada por 5 días por semana durante 8 semanas (20 mg/kg), junto al entrenamiento aeróbico en la estera (9,75 m/min) por 60 minutos por día. El músculo gastrocnemio colectado fue cortado y colorido por el método Hematoxilina-Eosina y sometido a una reacción histoquímica para verificar la actividad mitocondrial. Los datos fueron analizados utilizando el test t pareado, análisis de la variancia e Pos-Hoc de Scheffé, adoptándose p<0,05. Se verifico la presencia de alteraciones histológicas más significativas en los animales medicados y ejercitados, siendo también mayor la frecuencia de ocurrencia. El análisis histoquímica apunto que los grupos medicados presentaron fibras con actividad mitocondrial más intensa, al lado de fibras con pérdida de reacción. Los resultados de la morfometría no mostraron diferencias significativas entre los grupos estudiados. Se puede sugerir que la simvastatina es un medicamento que lleva a la ocurrencia de lesiones musculares e que su administración concomitante con la práctica de actividad física puede exacerbar estas lesiones, pudiendo tal hecho, estar relacionado con la respiración celular.

Effects of statin and aerobic physical exercise association in the cardiomyocytes of the rat: morphometric study / Efectos de la asociación de estatina y del ejercicio aeróbico en los cardiomiocitos de rata: estudio morfométrico

Physical exercise and statins, recommended interventions to dyslipidaemia treatment, are independently related to cardiomyocytes alterations, characterized by miocardic hypertrophy and apoptosis, respectively. Thus, the objective of the present study was to analyze the effects of statin and aerobic physical exercise association in the morphometric parameters of cardiac cell nucleus. 40 male rats adults were divided into four groups: exercised (DE); sedentary (DS), exercised and statin use (DES); sedentary and statin use (DSS). The animals received during the whole experimental period a hiperlipidic diet added 20 percent of coconut oil and 1.25 percent of cholesterol; after 30 days of its ingestión, a blood collection was made to verify the dyslipidaemia. Simvastatin (20 mg) was taken five days a week, during eight weeks. During this period, the animals exercised 60 minutes daily in the treadmill. After the last day of the protocol, the cardiac muscle was collected and maintained in liquid nitrogen (-180°C); the cuts were stained by Hematoxilin-Eosin method, and the cardiac fibers were submitted to the nuclear morphometric analyses. The data were analyzed using descriptive analyses, paired T test, Kruskal-Wallis test and Dunn post hoc test; for all analyses, it was adopted p<0.05. It was verified that the group receiving statin presented values statistically significant in comparison to the other groups, in the tridimensional and linear variables. The exercised and statin group, the values obtained in the morphometric analyses were similar to the control group. It is suggested that statins alone can cause alterations in the nucleus of cardiac cells that can be related to apoptosis occurrence and, when exercise is practiced associated to statin administration, the effects of statin can be reduced, what can be related to beneficial adaptations of cardiac mitochondrial in response to physical exercise, turning them more resistant to apoptotic stimuli.

El ejercicio físico y las estatinas, intervenciones recomendadas para tratamiento de la dislipidemia, están independientemente relacionadas con las alteraciones de los cardiomiocitos, que se caracterizan por hipertrofia miocárdica y apoptosis, respectivamente. El objetivo del presente estudio fue analizar los efectos de la asociación de estatinas y el ejercicio físico aeróbico en los parámetros morfométricos del núcleo de células cardíacas. 40 ratas macho adultas se dividieron en cuatro grupos: ejercitadas (DE); sedentarias (DS), ejercitadas y con uso de estatina (DES), sedentarias y con uso de estatina (DSS). Los animales recibieron durante todo el período experimental una dieta hiperlipidemica añadiendo 20 por ciento de aceite de coco y 1,25 por ciento de colesterol. Después de 30 días de su ingestión, se les extrajo sangre para verificar la dislipidemia. Los ejemplares ingirieron Simvastatina (20 mg) cinco días a la semana, durante ocho semanas. Durante este período, los animales ejercitaron 60 minutos diarios en la rueda de andar. Después del último día del protocolo,los animales fueron sacrificados y se les extrajo músculo cardiaco que fue mantenido en nitrógeno líquido (-180°C). De este material se obtuvieron cortes que fueron teñidos por el método de hematoxilina-eosina y las fibras cardiacas fueron sometidas a análisis morfométrico nuclear. Los datos fueron analizados mediante el análisis descriptivo, prueba de la t de Student, prueba de Kruskal-Wallis y Dunn test post hoc. Para todos los análisis fue aprobado p <0,05. Se comprobó que el grupo que recibió estatinas presentó valores estadísticamente significativos en comparación con los otros grupos, en las variables lineales y tridimensionales. En el grupo ejercitado y estatina, los valores obtenidos de los análisis morfométricos fueron similares a los del grupo control. Se sugiere que las estatinas, por sí solas, pueden causar alteraciones en el núcleo de las células cardiacas ...

Histometric study of alveolar bone in rats submitted to ethanol during lactation

The present work studied the adverse effects of maternal exposure of rats to alcohol during lactation, on the development of their off spring. Histometric evaluation by karyometry and of the alveolar bone at the level of the first upper molar of the sucking was perfomed. Two groups of animals, one coming from mothers exposed to drinking water containing 20 percent ethanol during the total lactation period and the other of controls coming from mothers receiving only alcohol-free drinking water during this period. On the 21 first day of lactation the young of each group were aleatorily selected and following anesthesia, their heads severed; after histological treatment, serial 6 ìm sections on the frontal plane at the molar level, stained with hematoxilin and eosin, were obtained. The experimental results produced, suggest that sucking from ethanol-treated mothers, show retarded post-natal growth, their alveolar bones presenting scarce, little calcified trabeculae, and a more abundant bone marrow compared to controls.

Considerando que la lactancia es un período importante y vulnerable, y que la exposición materna al alcohol durante esta fase puede provocar efectos adversos en las crías en desarrollo, el propósito del presente trabajo es evaluar histométricamente (mediante cariometría y estereología), el hueso alveolar a nivel del primer molar superior, de ratas lactantes sometidas a los efectos del etanol. Con esa finalidad utilizamos dos grupos, uno que recibió etanol al 20 por ciento en el bebedero, durante todo el período de lactancia (21días), y otro que recibió solo agua. En el 21° día de lactancia, 5 ratas de cada grupo fueron aleatoriamente seleccionadas. Después de sacrificados, los animales fueron fijados en formol al 10 por ciento. Las cabezas, separadas de los cuerpos, fueron incluidas en parafina, y cortadas seriadamente con 6 Lim de grosor, a partir de un plano frontal al nivel de los molares, y teñidas con hematoxilina y eosina. Basados en los resultados presentes, es posible concluir que el etanol al 20 por ciento en el agua de beber, administrado a ratas lactantes, provoca los siguientes efectos: reducción significativa del peso corporal, alteraciones de las trabéculas del hueso alveolar, observadas estereológicamente, evidenciadas por trabéculas delicadas y poco calcificadas, con médula abundante, núcleos menores en osteoblastos y osteocitos y más achatados en los primeros, y con osteocitos de volúmenes citoplasmático y celular menor y densidad numérica mayor.

Evaluation of epithelial cell proliferating activity and fibroblast nuclear kariometry in recurrent pterygium treated with mitomycin C.

PURPOSE: To evaluate the effectiveness of mitomycin C (MMC) in preventing recurrence of pterygium following conjunctival autograft transplantation (CAT). Ki-67 antigen to evaluate epithelial cell proliferation and fibroblast nuclear kariometry were used to assist treatment evaluation. METHODS: Twenty-nine patients with recurrent pterygium were divided into three groups: Group (G) 1--CAT and placebo eyedrops (PED); G2--CAT, 0.015% MMC subconjunctivally, and PED; G3--CAT and 0.02% MMC eyedrops. Immunohistochemistry for the Ki-67 antigen and fibroblast nuclei kariometry were performed on the excised tissue, divided into nasal and temporal sides. Kariometry was evaluated in terms of volume (Vl) and area (Ar) using at least 50 cells/patient. RESULTS: The percentage of positive epithelial cells for the Ki-67 antigen on the nasal and temporal side after treatment of the three groups were: nasal (5.39% G1, 4.49% G2, and 3.88% G3); temporal (3.30% G1, 4.46% G2, 4.14% G3), did not show significant differences. Fibroblast nucleus kariometry was: nasal Vl (792.1 mu3 G1, 605.1 mu3 G2, and 549.9 mu3 G3) and Ar (100.58 mu2 G1, 83.13 mu2 G2, and 78.41 mu2 G3). The three groups showed significant differences: p=0.039 and p=0.035, for respectively Vl and Ar, on the nasal side. After a six month of treatment, the three groups presented the following recurrence rates: G1, 22.22%, G2, 18.18% and G3, 33.33%, respectively. CONCLUSION: MMC did not reduce the number of positive epithelial cells for the Ki-67 antigen in recurrent pterygium, but decreased fibroblast nucleus volume and area on the nasal side of the pterygia. The number of positive epithelial cells for the Ki-67 antigen seemed not to be related to pterygium recurrence observed over a six-month post-surgery period. The role of epithelial cell proliferation in pterygium recurrence should be evaluated by further studies.

Toxicidade gonadal induzida pelo tratamento oncológico / Gonadal toxicity induced by oncological treatment

A incidência de neoplasias malignas no Brasil e no mundo vem aumentando a cada ano. Fatores como o aumento da expectativa de vida, a industrialização, a urbanização e os avanços tecnológicos estão diretamente relacionados com esse aumento. Por outro lado, o armamentário terapêutico, do qual se dispõe, permite a cura em alguns tipos de câncer e importante aumento na sobrevida em muitos outros. Entretanto, a citotoxicidade inerente ao tratamento das doenças malignas incorre, geralmente, em infertilidade. Quando do diagnóstico de uma neoplasia maligna, grande parte dos pacientes são jovens e ainda não estão com a sua prole constituida. Este artigo propõe uma reflexão a respeito da incidência de neoplasias malignas em indivíduos em idade fértil e sobre a obrigatoriedade de se abordar a questão da infertilidade relacionada ao tratamento oncológico, com o paciente, previamente à sua realização. Controvérsias sobre a qualidade dos tecidos reprodutivos de indivíduos afetados face às técnicas convencionais e modernas de reprodução assistida e criopreservação também são discutidas.

Evaluation of epithelial cell proliferating activity and fibroblast nuclear kariometry in recurrent pterygium treated with mitomycin C / Avaliação da atividade proliferativa das células epiteliais e da cariometria do núcleo dos fibroblastos em pterígios recidivados previamente tratados com a mitomicina C

PURPOSE: To evaluate the effectiveness of mitomycin C (MMC) in preventing recurrence of pterygium following conjunctival autograft transplantation (CAT). Ki-67 antigen to evaluate epithelial cell proliferation and fibroblast nuclear kariometry were used to assist treatment evaluation. METHODS: Twenty-nine patients with recurrent pterygium were divided into three groups: Group (G) 1 - CAT and placebo eyedrops (PED); G2 - CAT, 0.015 percent MMC subconjunctivally, and PED; G3 - CAT and 0.02 percent MMC eyedrops. Immunohistochemistry for the Ki-67 antigen and fibroblast nuclei kariometry were performed on the excised tissue, divided into nasal and temporal sides. Kariometry was evaluated in terms of volume (Vl) and area (Ar) using at least 50 cells/patient. RESULTS: The percentage of positive epithelial cells for the Ki-67 antigen on the nasal and temporal side after treatment of the three groups were: nasal (5.39 percent G1, 4.49 percent G2, and 3.88 percent G3); temporal (3.30 percent G1, 4.46 percent G2, 4.14 percent G3), did not show significant differences. Fibroblast nucleus kariometry was: nasal Vl (792.1 µ3 G1, 605.1 µ3 G2, and 549.9 µ3 G3) and Ar (100.58 µ2 G1, 83.13 µ2 G2, and 78.41 µ2 G3). The three groups showed significant differences: p=0.039 and p=0.035, for respectively Vl and Ar, on the nasal side. After a six month of treatment, the three groups presented the following recurrence rates: G1, 22.22 percent, G2, 18.18 percent and G3, 33.33 percent, respectively. CONCLUSION: MMC did not reduce the number of positive epithelial cells for the Ki-67 antigen in recurrent pterygium, but decreased fibroblast nucleus volume and area on the nasal side of the pterygia. The number of positive epithelial cells for the Ki-67 antigen seemed not to be related to pterygium recurrence observed over a six-month post-surgery period. The role of epithelial cell proliferation in pterygium recurrence should be evaluated by further studies.

OBJETIVO: Avaliar a eficácia da mitomicina C (MMC) na prevenção da recorrência quando previamente utilizada no transplante autólogo de conjuntiva (TAC). A avaliação da proliferação celular epitelial pelo antígeno Ki-67 e a cariometria do núcleo dos fibroblastos foram usados como auxiliares na avaliação do tratamento. MÉTODOS: Vinte e nove pacientes com pterígio recidivado foram divididos em três grupos: Grupo (G) 1-TAC e colírio placebo (PLA); G2-TAC, MMC 0,015 por cento subconjuntival e PLA; G3-TAC e colírio de MMC 0,02 por cento. A imuno-histoquímica foi realizada no tecido excisado para o antígeno Ki-67, como a cariometria dos núcleos dos fibroblastos (divididos em lado nasal e temporal). A cariometria dos núcleos dos fibroblastos foi avaliada de acordo com os seguintes parâmetros: volume (Vl) e área (Ar) em pelos menos 50 células por paciente. RESULTADOS: A porcentagem das células epiteliais positivas para o antígeno Ki-67 no lado nasal e temporal após o tratamento dos três grupos estudados foi: nasal (3,30 por cento G1, 4,49 por cento G2 e 3,38 por cento G3) e temporal (3,30 por cento G1, 4,46 por cento G2 e 4,14 por cento G3) não mostrando diferença significativa. A cariometria do núcleo dos fibroblastos foi: Vl nasal (792,1 µ3 G1, 605,1 µ3 G2, e 549,9 µ3 G3) e a Ar (100,58 µ2 G1, 83,13 µ2 G2, e 78,41 µ2 G3). Os três grupos mostraram uma diferença significativa p=0,039 e p=0,035, respectivamente do Vl e da Ar no lado nasal. Após seis meses de tratamento, os três grupos apresentaram a seguinte taxa de recidiva: 22,22 por cento G1, 18,18 por cento, G2 e 33,33 por cento G3 respectivamente. CONCLUSÃO: O uso da MMC não interferiu nas células epiteliais positivas para o antígeno Ki-67 no pterígio recidivado, mas acarretou diminuição do volume e área dos núcleos dos fibroblastos no lado nasal do pterígio. As células epiteliais positivas para o antígeno Ki-67 parecem não ter relação com a recidiva do pterígio após seis meses...

Effects of Aspartame on Fetal Kidney: A Morphometric and Stereological Study / Efectos del Aspartame en el Riñon Fetal: Estudios Morfométrico y Estereológico

The objective of this study was the evaluation of aspartame effects on morphometric alterations of the glomerulus, proximal and distal convoluted tubules and collecting ducts of the rat fetal kidney during organogénesis. Fifteen pregnant rats averaging 24 g body weight, were divided into 3 groups (n=5 each) of controls, rats treated with aspartame exposed to room temperature and rats treated with aspartame heated to 40°C. Animals were given 14mg / kg aspartame by the intragastric route on the 9th, 10th, and 11th days of pregnancy. Karyometric and stereological techniques estimated morphological changes. A significant decrease of fetal body weight was observed in the group given aspartame kept at room temperature, compared to controls. Karyometry permitted the estimation of the significant nuclear variations observed in the cells of the glomerulus, proximal and distal convoluted tubules and collecting ducts of aspartame-treated rat fetuses. Stereolgical parameters showed statistically significantly increased cell volume and decreased numerical cell density in fetal kidneys of rats treated with aspartame heated to 40° compared to controls. These results indicate that the use of aspartame leads to alterations in all renal structures studied, suggesting this product's nephrotoxicity.

El objetivo de este estudio fue evaluar las alteraciones morfológicas del aspartame en glomérulos, túbulos contorneados distal y proximal y ductos colectores, en ríñones de ratas, durante la organogénesis. Se utilizaron ratas preñadas con un peso promedio de 24g, las que fueron separadas en 3 grupos (n=5 cada uno): un grupo control, otro grupo con ratas tratadas con aspartame y expuestas a temperatura ambiente y un grupo de ratas tratadas con aspartame y mantenidas a 40° C. A los animales se les administró 14 mg/kg de aspartame vía intragástrica en las semanas 9, 10 y 11 de preñez. Con técnicas cariométricas y estereológicas se estimaron los cambios morfológicos. Una disminución significativa del peso fetal se observó en el grupo que recibió aspartame y mantenida a temperatura ambiente, comparado con los controles. La cariometría permitió la estimación de significativas variaciones nucleares observadas en las células de los glomérulos, túbulos contorneados distal y proximal y ductos colectores, en los fetos de las ratas tratadas con aspartame. Los parámetros estereológicos mostraron un incremento estadísticamente significativo del volumen celular y una disminución en la densidad de número de las células, en ríñones fetales de ratas tratadas con aspartame y mantenidas a 40° C comparado con los controles. Estos resultados indican que el uso del aspartame lleva consigo alteraciones en todas las estructuras renales estudiadas, lo que sugiere la nefrotoxicidad del producto.

Histometric Study of the Epithelium of Rats Submitted to Ethanol During Lactation / Estudio Histométrico del Epitelio de Ratas Sometidas al Etanol Durante la Lactancia

The present work studied the adverse effects of maternal exposure of rats to alcohol during lactation, on the development of their offspring. Histometric evaluation by karyometry and of the palatine epithelium of the sucking was performed. Two groups of animals, one coming from mothers exposed to drinking water containing 20% ethanol during the total lactation period and the other of controls coming from mothers receiving only alcohol-free drinking water during this period. On the 21 first day of lactation the young of each group were aleatorily selected and following anesthesia, their heads severed; after histological treatment, serial 6 -J,m sections on the frontal plane at the molar level, stained with hematoxilin and eosin, were obtained. The experimental results produced, suggest that suckling from ethanol-treated mothers, show a significant decrease of body weight, significant alterations of karyometric and stereological measurements that determined hypotrophy of palatine epithelial cells and toxicity of ethanol at the palatine epithelium.

El presente trabajo tiene por objetivo estudiar en ratas los efectos adversos de la exposición materna al alcohol durante la lactancia, en el desarollo de sus crías. Fue evaluado histométricamente (cariometría y estereología) el epitelio palatino de las críass. Fueron utilizados dos grupos: uno tratado con etanol al 20% en agua de bebedero, durante toda la lactancia; y control, recibió solamente agua. En el día 21° de la lactancia, cinco crías de cada uno de los grupos, fueron seleccionadas al azar, anestasiadas las cabezas de ellas fueron separadas de los cuerpos. Después del tratamiento histológico, fueron obtenidos cortes seriados de 6 um del plano frontal, a nivel de los molares y coloreados con hematoxilina eosina. Los resultados sugieren que lactantes de las madres tratadas con etanol al 20% en el bebedero, presentaron disminución significativa del peso corporal, alteraciones importantes de las medidas cariométricas y estereológicas, que determinaron hipotrofia de las células epiteliales del paladar y toxicidad del etanol en el epitelio palatino.

Effects of Aspartame on Maternal-Fetal and Placental Weights, Length of Umbilical Cord and Fetal Liver: A Kariometric Experimental Study / Efectos del Aspartame sobre el Peso Materno-Fetal y Placentario, Largo del Cordón Umbilical e Hígado Fetal: Un Estudio Cartométrico Experimental

Aspartame is a synthetic sweetener consumed by more than half the adult population in 75 countries. Their metabolites can be toxic, principally to the liver and retina, and there are few studies on the use of aspartame in gestation. Twenty pregnant rats were weighed and allocated randomly (n=5 per group) to receive 14 mg/kg aspartame or water by oral-gastric drip. Treated Tl: aspartame diluted in water at room temperature; Treated T2: aspartame diluted in water heated to 40° C; control Cl: water at room temperature; and control C2: water heated to 40° C. Placentas were weighed, umbilical cords measured and 1000 nuclei of fetal hepatocytes (250 from each group) were analyzed morphometrically utilizing the technique of kariometry, with application of the Mann-Whitney U-Test. There were reductions in mean placental and maternal-fetal weights, in umbilical-cord length, and the majority of kariometric parameters of the hepatocytes in the group treated with aspartame diluted in distilled water at room temperature. Reduction of placental and maternal-fetal weights occurred, shortening of the umbilical cord, and decrease in kariometric parameters in fetal hepatocyte nuclei after administration of aspartame diluted in distilled water at 40°C temperature. The use of aspartame during gestation can be prejudicial to the fetus.

El aspartame es un endulzante sintético consumido por más de la mitad de la población adulta, en 75 países. Sus metabolitos pueden ser tóxicos, principalmente en el hígado y retina y hay algunos estudios sobre el aspartame en el embarazo. Veinte ratas preñadas fueron pesadas y distribuidas aleatoriamente (n=5 por grupo) y recibieron 14 mg/Kg de aspartame o agua por vía oral- gástrica. Tratamiento 1: aspartame diluido en agua a temperatura ambiente; Tratamiento T2: aspartame diluido en agua tibia a 40 °C; control Cl: agua a temperatura ambiente, y control C2: agua tibia a 40° C. Las placentas fueron pesadas, el cordón umbilical medido y 1000 núcleos de hepatocitos fetales (250 de cada grupo) se analizaron morfométricamente utilizando la técnica de canometría con aplicación del Test U de Mann-Whitney U-Test. En el grupo tratado con aspartame diluido en agua a temperatura ambiente, hubo reducción en los pesos promedios de la placenta y materno-fetal, largo del cordón umbilical y en la mayoría de los parámetros cartométricos de los hepatocitos. Lo mismo ocurrió en el grupo tratado con aspartame diluido en agua a 40 °C. El uso del aspartame durante las gestación puede ser perjudicial para el feto.

Study of the Nuclear Volume of Testicular Cells of Rats Receiving Ofloxacin Through Lactation / Estudio del Volumen Nuclear de Células Testiculares de Ratas que Recibieron Ofloxacin Durante la Lactancia

Ofloxacin presents an ample spectrum of antimicrobial action, including combating Mycobacterium leprae, and is currently employed as a substitute when the use of rifampicin is impossible. The objective of this work was to study alterations in testicular cell nuclei of suckling rats, whose dams were submitted to oral application of ofloxacin, and respective control groups. The method utilized was morphometry by the karyometric technique. The main structures observed in histological preparations of the testicles were interstitial cells, spermatogonias, and sustentacular cells. 10 Wistar rats were utilized, four treated and five controls, in the period of the first 25 days of life, whose dams received ofloxacin 12 mg/ Kg of body weight / day orally, before being killed on the 25th day after birth. The karyometric study of interstitial cells and spermatogonias revealed that there were no changes in the form of their nuclei (p > 0.05). Since sustentacular cell nuclei presented increased major diameter, minor diameter, mean geometric diameter, volume, area, volume/area ratio and perimeter, as well as an augmented and statistically different eccentricity (p < 0.05) in suckling pups whose dams were administered ofloxacin, the nuclei presented larger size and more elongated form. It was concluded that the sustentacular cells were more sensitive to the ofloxacin effect at the administered dose.

El ofloxacin presenta un amplio espectro de acción antimicrobiana, incluyendo el combate a.Mycobacterium leprae, y es frecuentemente empleado como un sustituto cuando el uso de la rifampicina es imposible. El objetivo del trabajo fue estudiar las alteraciones en el núcleo de las células testiculares en ratas que se encontraban amamantando y que fueron sometidas a la aplicación oral de ofloxacin. El método utilizado fue la técnica morfométrica de la cariometría. Las principales estructuras observadas en las preparaciones histológicas fueron las células intersticiales, espermatogenias y células sustentaculares. Se utilizaron 10 ratas Wistar, cinco fueron el grupo control y cinco sometidas al tratamiento, cuyas madres recibieron ofloxacin en dosis oral diaria de 12 mg/Kg de peso corporal los primeros 25 días de vida, para luego ser sacrificadas al día 25 después del nacimiento. El estudio cariométrico de las células intersticiales y de la espermatogénesis revelaron que no hubo cambios en la forma de sus núcleos (p > 0,05). Las células sustentaculares presentaron un incremento en su diámetro mayor, diámetro menor, diámetro geométrico promedio, volumen, área, razón volumen/área y perímetro, también hubo aumento con una diferencia de la excentricidad estadísticamente significativa (p < 0,05) en las crías amamantadas, a las cuales se les administró ofloxacin. Los núcleos presentaron un gran tamaño y una forma más alargada. Esto concluye que las células sustentaculares son más sensibles al efecto de la administración de ofloxacin.

Effect of Swimming Training on the Rectus Abdominis Muscle of rats: Morphological and Histochemical Aspects / Efecto de la Natación Sobre el Músculo Recto del Abdomen de la Rata: Aspectos Morfológicos e Histoquímicos

We investigated the effect of swimming training in rats on morphological characteristics, hypertrophy levels and metabolic and contractile adaptations of different fiber types in rat the rectus abdominis muscle. Rats were randoverly assigned to one of three groups (N = 5 each): a) swimming training for 1 h, twice a week (2x/w), b) 1 h five times a week (5x/w) for 9 consecutive weeks, or c) without any swimming training (Control). Body weight increased in 2x/w rats and decreased in the 5x/w ones. Muscle fiber diameters increased in both trained groups, with higher values in the 2x/w group. Aerobic exercise increased slow oxidative (SO) + fast-oxidative-glycolytic (FOG) fibers and decreased fast glycolytic (FG) fibers. In addition, SO fibers were increased and FOG + FG fibers were decreased in trained rats. Small and angulated atrophic fibers were also observed. These results corroborate that swimming exercise increases aerobic metabolism and thus oxidative and low contraction fibers. However, the used protocol induced, to a variable degree, changes in the muscle fiber morphology.

Se estudió el efecto de la natación en las características morfológicas, niveles de hipertrofia y las adaptaciones metabólicas y contráctiles de diferentes tipos de fibras en el músculo recto del abdomen de ratas. Las ratas fueron asignadas en tres grupos (N = 5 cada uno): a) natación por 1 hora dos veces a la semana (2x/s), b) 1 hora, cinco veces por semana (5x/s) por nueve semanas consecutivas y c) sin natación (control). El peso corporal se incrementó en las ratas 2x/s y disminuyó en 5x/s. El diámetro de las fibras musculares aumentó en ambos grupos entrenados, con mayores valores en las ratas 2x/s. El ejercicio aeróbico incrementó las fibras de oxidación lenta (OL) + las fibras de glicólisis oxidativa rápida (GOR) y disminuyeron las fibras de glicólisis rápida (GR). Además, las fibras OL aumentaron y las fibras GOR y GR disminuyeron en las ratas entrenadas. Se observó una pequeña atrofia y deshidratación de las fibras. Estos resultados corroboran que la práctica de la natación incrementa el metabolismo aeróbico, las fibras de contracción lenta y la oxidación. Sin embargo, el protocolo utilizado induce cambios en grado variable en la morfología de las fibras musculares.