Tatiane Kamada Errero

Comparison of low level laser, ultrasonic therapy and association in joint pain in Wistar rats

INTRODUCTION Both therapeutic ultrasound as a low level laser therapy are used to control musculoskeletal pain, despite controversy about its effects, yet the literature is poor and also presents conflicting results on possible cumulative effects of techniques association. The aim was to compare the antinociceptive effects of low level laser therapy, therapeutic ultrasound and the association. METHODS 24 Wistar rats were divided into: GPL--induction of hyperesthesia in the right knee, and untreated; GUS--treated with therapeutic ultrasound (1 MHz, 0.4 W/cm2) GL--low intensity laser (830 nm, 8 J/cm2); GL+US--treated with both techniques. To produce the hyperesthesia 100 μl of 5% formalin solution were injected into the tibiofemoral joint space, which was assessed by von Frey filament digital before (EV1), 15 (EV2), 30 (EV3) and 60 (EV4) minutes after induction. RESULTS In comparison within groups, for the withdrawal threshold when the fi lament was applied to the knee, the back to baseline was observed only for GUS. Comparisons between groups were not different in EV3, and GL was higher than GPL. In EV4 the three groups effectively treated were higher than placebo. On withdrawal threshold on the plantar surface, GL showed return to baseline values already in EV3, and GUS and GL+US returned in EV4. Comparing the groups in EV3 there was a significantly lower threshold to compare GPL with GL and GUS (p <0.05), and there was only EV4 differences when comparing GPL with GUS. CONCLUSION Both modalities showed antinociceptive effects.

Influence of low-level laser therapy on vertical jump in sedentary individuals

Objective To investigate the effects of low intensity laser (660nm), on the surae triceps muscle fatigue and power, during vertical jump in sedentary individuals, in addition to delayed onset muscle soreness. Methods We included 22 sedentary volunteers in the study, who were divided into three groups: G1 (n=8) without performing low intensity laser (control); G2 (n=7) subjected to 6 days of low intensity laser applications; and G3 (n=7) subjected to 10 days of low intensity laser applications. All subjects were evaluated by means of six evaluations of vertical jumps lasting 60 seconds each. In G2 and G3, laser applications in eight points, uniformly distributed directly to the skin in the region of the triceps surae were performed. Another variable analyzed was the delayed onset muscle soreness using the Visual Analog Scale of Pain. Results There was no significant difference in fatigue and mechanical power. In the evaluation of delayed onset muscle soreness, there was significant difference, being the first evaluation higher than the others. Conclusion The low intensity laser on the triceps surae, in sedentary individuals, had no significant effects on the variables evaluated.

Avaliação da força de preensão em ratos Wistar, normais e obesos, submetidos à natação com sobrecarga após compressão do nervo mediano

OBJECTIVE To verify the functionality through muscle grip strength in animals with obesity induced by monosodium glutamate (MSG) and in control animals, which suffered compression of the right median nerve, and treated with swimming with overload. METHODS During the first five days of life, neonatal Wistar rats received subcutaneous injections of MSG. The control group received a hypertonic saline solution. Forty-eight rats were divided into six groups: G1 (control); G2 (control + injury); G3 (control + injury + swimming); G4 (obese); G5 (obese + injury); G6 (obese + injury + swimming). The animals in groups G2, G3, G5 and G6 were submitted to compression of the median nerve and G3 and G6 groups were treated, after injury, with swimming exercise with load for three weeks. The swimming exercise had a progressive duration, according to the week, of 20, 30 and 40minutes. Muscle strength was assessed using a grip strength meter preoperatively and on the 3rd, 7th, 14th and 21st days after surgery. The results were expressed and analyzed using descriptive and inferential statistics. RESULTS When the grip strength was compared among assessments regardless of group, in the second assessment the animals exhibited lower grip strength. G1 and G4 groups had greater grip strength, compared to G2, G3, G4 and G6. CONCLUSION The swimming exercise with overload has not been effective in promoting improvement in muscle grip strength after compression injury of the right median nerve in control and in obese-MSG rats.

Artigo originalAvaliação da força de preensão em ratos Wistar, normais e obesos, submetidos à natação com sobrecarga após compressão do nervo medianoEvaluation of grip strength in normal and obese Wistar rats submitted to swimming with overload after median nerve compression☆

OBJECTIVE To verify the functionality through muscle grip strength in animals with obesity induced by monosodium glutamate (MSG) and in control animals, which suffered compression of the right median nerve, and treated with swimming with overload. METHODS During the first five days of life, neonatal Wistar rats received subcutaneous injections of MSG. The control group received a hypertonic saline solution. Forty-eight rats were divided into six groups: G1 (control); G2 (control + injury); G3 (control + injury + swimming); G4 (obese); G5 (obese + injury); G6 (obese + injury + swimming). The animals in groups G2, G3, G5 and G6 were submitted to compression of the median nerve and G3 and G6 groups were treated, after injury, with swimming exercise with load for three weeks. The swimming exercise had a progressive duration, according to the week, of 20, 30 and 40minutes. Muscle strength was assessed using a grip strength meter preoperatively and on the 3rd, 7th, 14th and 21st days after surgery. The results were expressed and analyzed using descriptive and inferential statistics. RESULTS When the grip strength was compared among assessments regardless of group, in the second assessment the animals exhibited lower grip strength. G1 and G4 groups had greater grip strength, compared to G2, G3, G4 and G6. CONCLUSION The swimming exercise with overload has not been effective in promoting improvement in muscle grip strength after compression injury of the right median nerve in control and in obese-MSG rats.

Behavioral assessment of rats through the forced-swimming test

Objetivos: O exercicio fisico regular tem diversos efeitos beneficos, contudo, ha relatos de aumento na concentracao de corticosteroides endogenos, os quais podem inibir a neurogenese e piorar as funcoes cognitivas, sendo este um aspecto dubio do exercicio fisico. O objetivo deste estudo foi avaliar, por meio de testes comportamentais, o efeito do exercicio cronico por natacao forcada com e sem sobrecarga, sobre parâmetros de ansiedade em ratos Wistar. Metodos: Foram utilizados 24 ratos Wistar, separados em tres grupos: Grupo Controle – submetido apenas a avaliacoes e contato com a agua; Grupo Natacao – composto por animais submetidos a natacao com tempo progressivo; Grupo Natacao com Sobrecarga – composto por animais submetidos a natacao com sobrecarga de 10% do peso corporal. O exercicio ocorreu tres vezes por semana, no periodo vespertino, com aumento no tempo a cada duas semanas (20, 30 e 40 minutos), totalizando seis semanas. Foi realizado em um tanque de agua circular de 200 litros, com profundidade de 50 cm e temperatura da agua mantida entre 30 e 32o C. A ansiedade dos animais foi avaliada pelos testes Labirinto em Cruz Elevado e Campo Aberto. Resultados: Nao houve diferencas significativas em qualquer dos testes comportamentais, comparando os tres grupos. Conclusoes: Nao houve alteracao no padrao comportamental de ratos Wistar submetidos a diferentes protocolos de exercicio (natacao forcada com e sem sobrecarga) quando comparados ao grupo controle nao submetido a exercicios

Swimming does not alter nociception threshold in obese rats submitted to median nerve compression

Objectives: We, herein, analyzed the effect of swimming on nociception threshold and peripheral nerve regeneration in lean and obese rats submitted to median nerve compression. Methods: To induce obesity, newborn male Wistar rats received injections of monosodium glutamate (MSG), whereas the control (CTL) group received saline. The animals were separated into 6 groups; control and obese (CTL and MSG), control and obese with lesion (CTL LES and MSG LES), and control and obese with lesion submitted to physical exercise (CTL LES PE and MSG LES PE). Results: Median nerve compression reduced nociception threshold in CTL LES and MSG LES rats. Swimming effectively altered nociception only in CTL LES PE animals. Lean and obese animals displayed histological differences, when compared to sedentary animals, and exercise improved axon regeneration in both groups. The brain-derived neurotrophic factor and GAP 43 protein expression was greater in animals submitted to nervous compression without alteration by exercise. Discussion: In conclusion, swimming, a conservative treatment for peripheral nerve lesions, was not able to improve the nociception threshold in obese rats.