Bruno Pogorzelski Rocha

Avaliação do exercício físico como fator de analgesia em um modelo experimental de ciatalgia

OBJECTIVE: To evaluate the efficacy of physical exercise (swimming and jumping), with and without overload, working in reducing the pain of rats undergone to an experimental model of sciatica. METHODS: 24 rats were divided into four groups: Placebo (GP), Swimming Group (NG) Swimming 10% Group (GN10) and Leap Group (GS). All groups were submitted to the experimental sciatica model and assessed for pain post-exercise for the Functional Disability Test and the Von Frey filament. RESULTS: In comparison within groups there were significant differences in the moments after injury with the pre-injury, for both assessment instruments. With Von Frey filament was observed a significant difference in group GN10 and GS in the final moments of evaluation. In comparisons between groups were not statistically significant differences obtained with any assessment instrument. CONCLUSION: Treatment with physical exercise was not effective in reducing pain in rats subjected to experimental sciatica model.

Avaliação do papel de opioides endógenos na analgesia do laser de baixa potência, 820 nm, em joelho de ratos Wistar

BACKGROUND AND OBJECTIVES: Pain may result in incapacity when it is associated to structural injury. Low power laser is useful in therapies aiming at decreasing joint pain and at tissue repair, but it is still somewhat controversial. This study aimed at evaluating whether analgesia induced by 820 nm low power laser is affected by the application of an endogenous opioids inhibitor. METHOD: Twenty-four Wistar rats submitted to hyperalgesia were divided into four groups. G1: untreated; G2: treated with 820 nm laser; G3: naloxone injection before injury and untreated; G4: naloxone and treated with 820 nm laser. To induce hyperalgesia, 100 µL of 5% formalin were injected in the right tibiofemoral joint space. Nociception was evaluated by the time for flinching (TFF) in five moments: AV1 (pre-injury), AV2 (15 min/after), AV3 (30 min/after), AV4 (1 hour after) and AV5 (2 hours after). RESULTS: All groups showed significant difference between AV1 and AV2, but only G2 showed no difference between AV1 and AV3. There have been no differences for remaining moments as compared to AV1. CONCLUSION: Low power 820 nm laser analgesia is affected by naloxone.

Uso do exercício resistido antagonizado por naloxone como fator de analgesia em sinovite aguda de joelho de ratos Wistar

Analgesia arising from exercising can occur via release of endogenous opioids in the central nervous system and periphery. However, the literature remains controversial about exercise ways and actions in pain. Thus, the aim of this study was to evaluate whether resistance exercise produces changes on the nociception and suffers interference by applying an opioid inhibitor. 18 rats divided into three groups were used: G1 - hyperalgesia on right knee and untreated; G2 - hyperalgesia and treated with jumps in water; G3 - hyperalgesia with previous injection of naloxone and subsequent jumps. To produce hyperalgesia,100 ul of 5% formalin was injected in the tibiofemoral joint space. Pain was assessed using a digital von Frey filament on the right medial tibiofemoral joint. The evaluation periods were: pre-injury (EV1) after 15 minutes (EV2) and 30 minutes (EV3) and one hour (EV4). The applied exercise was jumping in water and it occurred after EV2. The animal performed 4 sets of 5 jumps, with an interval of 3 minutes and overload of 50% of body weight. In G1, nociceptive increase was observed, with significant decrease and return to initial baseline values in AV4; G2 showed threshold restoration after exercise and return to baseline; G3 reduced thresholds, without restoration or significant increase in them. We concluded that there was analgesia with use of exercise and that it was altered by blocking beta-endorphin.

Exercício resistido em meio aquático para ratos Wistar submetidos a trauma em tendão: avaliação da nocicepção e edema

BACKGROUND AND OBJECTIVES: Models of physical exercise for animals are useful tools to analyze organic functions difficult to be observed in humans, such as the evolution of pain after tendinous trauma. This study aimed at comparing the effects of resistance physical exercise on pain and edema in calcaneal tendons of rats submitted to trauma. METHOD: We used 18 Wistar rats divided in 3 groups: Control Group (CG, n = 6) - animals submitted to right calcaneal tendon trauma and untreated; Group 2 Jump (G2, n = 6) - animals submitted to trauma and treated with jumps in water, 2 series of 5 jumps; Group 3 Jump (G3, n = 6) - animals submitted to trauma and treated with jumps in water, 4 series of 5 jumps. To induce tendinous trauma, animals were anesthetized and received trauma with approximately 0.40 J in the lateral face of the calcaneal tendon. Jumps were performed daily with 24-hour intervals between applications. Digital Von Frey filament was used to assess pain and edema was assessed by tendon diameter variation with a caliper rule. RESULTS: Results have shown a slight advantage for G2, which has performed less repetitions of the exercise; for edema, however, there has been slight advantage for G3. CONCLUSION: Physical exercise has been slightly beneficial to decrease edema and pain.

Avaliação de parâmetros histomorfométricos em sóleos de ratos submetidos à remobilização por salto em meio aquático

INTRODUCTION: The muscular tissue is able to respond stimuli such as immobilization that induces hypotrophy altering muscle performance and are important methods that aim to reverse these deleterious effects in the post-immobilization. OBJECTIVE: The aim of this study was to evaluate transverse and longitudinal histomorphometric parameters of the soleus muscle fibers of rats immobilized in the shortened position and submitted to remobilization by jumping in water. METHODS: It was used 24 rats divided into 3 groups: G1 - remobilized freely, G2 - remobilized with jumps daily, and G3 - jumps on alternate days. The immobilization and remobilization occurred in 2 weeks for the right limb. The variables analyzed were: muscle mass, muscle fiber diameter, length and series sarcomeres estimate along the muscle. RESULTS: There was a reduction in muscle mass for both groups, to the diameter there was difference in G1 and G3, to the muscle length no significant differences, however, for the series sarcomeres estimate was found significant changes in all the groups. CONCLUSION: The protocol used has partial action against the deleterious effects of immobilization.

Avaliação de sóleos de ratas Wistar ooforectomizadas e remobilizadas em meio aquático

INTRODUCCION: a la incertidumbre sobre la manera mas eficaz de removilizacion de los musculos despues de periodos de inmovilizacion.OBJETIVO: Evaluar el comportamiento de removilizacion con natacion sobre parametros histomorfometricos del musculo soleo de ratas ooforectomizadas y pseudo ooforectomizadas.METODOS: Se utilizaron 24 ratas Wistar subdivididas en cuatro grupos: G1: sometidas a ooforectomia, inmovilizacion por 15 dias y removilizadas libremente; G2: ooforectomia, inmovilizacion y removilizadas con natacion por 10 dias; G3: pseudo ooforectomia, inmovilizacion y removilizadas libremente; G4: pseudo ooforectomia, inmovilizacion y removilizadas con natacion. Los musculos soleos derechos e izquierdos fueron disecados para analisis histomorfometricos longitudinal y transversal. El recuento de los sarcomeros se hizo en 300 micras y la longitud de la fibra muscular fue medida por paquimetro analogico. El peso muscular fue obtenido en balanza analitica y el diametro se realizo en 100 fibras por musculo.RESULTADOS: Hubo reduccion significativa tanto en el analisis longitudinal como en el transversal cuando se compararon los musculos soleos derechos e izquierdos de ambos grupos.CONCLUSION: La inmovilizacion del musculo soleo de ratas ooforectomizadas y pseudo ooforectomizadas causa efectos nocivos para la morfometria muscular y la removilizacion por medio de la natacion no fue capaz de promover el retorno de los patrones estructurales del musculo soleo.

Assessment of Wistar rats soleus ovariectomized and remobilized in water

INTRODUCCION: a la incertidumbre sobre la manera mas eficaz de removilizacion de los musculos despues de periodos de inmovilizacion.OBJETIVO: Evaluar el comportamiento de removilizacion con natacion sobre parametros histomorfometricos del musculo soleo de ratas ooforectomizadas y pseudo ooforectomizadas.METODOS: Se utilizaron 24 ratas Wistar subdivididas en cuatro grupos: G1: sometidas a ooforectomia, inmovilizacion por 15 dias y removilizadas libremente; G2: ooforectomia, inmovilizacion y removilizadas con natacion por 10 dias; G3: pseudo ooforectomia, inmovilizacion y removilizadas libremente; G4: pseudo ooforectomia, inmovilizacion y removilizadas con natacion. Los musculos soleos derechos e izquierdos fueron disecados para analisis histomorfometricos longitudinal y transversal. El recuento de los sarcomeros se hizo en 300 micras y la longitud de la fibra muscular fue medida por paquimetro analogico. El peso muscular fue obtenido en balanza analitica y el diametro se realizo en 100 fibras por musculo.RESULTADOS: Hubo reduccion significativa tanto en el analisis longitudinal como en el transversal cuando se compararon los musculos soleos derechos e izquierdos de ambos grupos.CONCLUSION: La inmovilizacion del musculo soleo de ratas ooforectomizadas y pseudo ooforectomizadas causa efectos nocivos para la morfometria muscular y la removilizacion por medio de la natacion no fue capaz de promover el retorno de los patrones estructurales del musculo soleo.

Evaluación de sóleos de ratas Wistar ooforectomizadas y removilizadas en medio acuático

INTRODUCCION: a la incertidumbre sobre la manera mas eficaz de removilizacion de los musculos despues de periodos de inmovilizacion.OBJETIVO: Evaluar el comportamiento de removilizacion con natacion sobre parametros histomorfometricos del musculo soleo de ratas ooforectomizadas y pseudo ooforectomizadas.METODOS: Se utilizaron 24 ratas Wistar subdivididas en cuatro grupos: G1: sometidas a ooforectomia, inmovilizacion por 15 dias y removilizadas libremente; G2: ooforectomia, inmovilizacion y removilizadas con natacion por 10 dias; G3: pseudo ooforectomia, inmovilizacion y removilizadas libremente; G4: pseudo ooforectomia, inmovilizacion y removilizadas con natacion. Los musculos soleos derechos e izquierdos fueron disecados para analisis histomorfometricos longitudinal y transversal. El recuento de los sarcomeros se hizo en 300 micras y la longitud de la fibra muscular fue medida por paquimetro analogico. El peso muscular fue obtenido en balanza analitica y el diametro se realizo en 100 fibras por musculo.RESULTADOS: Hubo reduccion significativa tanto en el analisis longitudinal como en el transversal cuando se compararon los musculos soleos derechos e izquierdos de ambos grupos.CONCLUSION: La inmovilizacion del musculo soleo de ratas ooforectomizadas y pseudo ooforectomizadas causa efectos nocivos para la morfometria muscular y la removilizacion por medio de la natacion no fue capaz de promover el retorno de los patrones estructurales del musculo soleo.