Central involvement of 5-HT1A receptors in antinociception induced by photobiomodulation in animal model of neuropathic pain.

This study aimed to investigate the central involvement of 5-HT1A receptors in the nociceptive behavior of mice submitted to the chronic constriction injury (CCI) of sciatic nerve and the subsequent application of photobiomodulation (PBM). Male mice (Swiss-albino) were submitted to CCI and subsequently received an infusion of WAY100635 (5-HT1A receptor antagonist) or intracerebroventricular saline (ICV), followed by infrared laser irradiation (808 nm), in continuous mode, with the power of 100 mW and a dose of 0 J/cm2 (control group) or 50 J/cm2. The thermal hyperalgesia was evaluated by hot plate test, while mechanical allodynia was evaluated by von Frey filaments. After CCI, animals showed a reduction in the nociceptive threshold (p<0.001) when compared to the sham group. In von Frey test, the CCI + saline + PBM 50 J/cm2 group showed an increase in nociceptive threshold (p<0.001) in all measurement moments in comparison with groups CCI + SALINE + PBM 0 J/cm2, CCI + WAY100635 + PBM 50 J/cm2, and CCI + WAY100635 + PBM 0 J/cm2. Similarly, in hot plate test, CCI + SALINE + PBM 50 J/cm2 group showed an increase in nociceptive threshold after application of PBM at 120 and 180 min. Because of the results found, it can be suggested the involvement of 5-HT1A receptors in the central nervous system, since WAY100635 was able to reverse the antinociceptive effect provided by PBM in animals submitted to CCI.

Intra-periaqueductal gray matter injections of midazolam fail to alter anxiety in plus-maze experienced mice.

It is well known that prior experience to the elevated plus-maze increases the avoidance of rodents to the open arms and impairs the anxiolytic-like effect of benzodiazepines evaluated during a subsequent exposure to the maze, a phenomenon known as "one-trial tolerance". Centrally injected benzodiazepine drugs attenuate anxiety in some limbic structures, such as hypothalamus, amygdala and the midbrain periaqueductal gray (PAG). This study investigated the effects of intra-PAG infusions of midazolam (MDZ) in maze-naïve and maze-experienced mice. The antiaversive effects of MDZ (3.0 nmol and 30 nmol in 0.1 microl) were evaluated by prior injection of flumazenil (16 nmol/0.1 microl), a benzodiazepine receptor antagonist, into the same midbrain site. Test videotapes were scored for conventional measures of anxiety and locomotor activity, as well as a range of ethological measures related to risk assessment. In maze-naïve mice, intra-PAG infusions of MDZ increased % open arm entries (3.0 nmol) and % open arm time (3.0 and 30 nmol). These effects were observed in the absence of significant changes in locomotor activity, indicating a selective anxiolytic-like effect of MDZ. The antiaversive effects of MDZ were completely blocked by prior injection of flumazenil which in turn did not alter any other behavioral measure. In maze-experienced mice, intra-PAG infusion of MDZ did not modify any behavioral measure. Taken together, present results corroborate previous studies demonstrating that GABA/benzodiazepine receptor complex located within the PAG plays a role on anxiety modulation in maze-naïve mice as well as indicate its involvement in the OTT phenomenon.

Effect of the Auricular Acupoint Associated with Physical Exercise in Elderly People: A Randomized Clinical Test.

OBJECTIVE: To analyze the effect of auricular acupoint associated with physical exercise on balance, mobility, and fear of falling in the elderly. METHOD: The study is characterized as a clinical, controlled, and randomized trial with 22 elderly people divided into two groups: kinesiotherapy group (n = 11) and kinesiotherapy/auriculotherapy group (n = 11). The instruments used for evaluation were Falls Efficacy Scale International; Berg Balance Scale, and Timed up and Go Test. The intervention was performed with frequency 2×/week for 8 weeks. In the kinesiotherapy/auriculotherapy group, in addition to kinesiotherapy, auriculotherapy was applied in specific acupoints. The Shapiro-Wilk test was used to determine the normality of the data, and for comparison, analysis of variance was used for repeated measures of two factors. RESULTS: There was a significant intragroup reduction for the Timed up and Go Test (p = 0.00) and Falls Efficacy Scale International (p = 0.00), and significant intragroup Berg Balance Scale (p = 0.00) for both groups. CONCLUSION: The auricular acupoint did not influence the balance, mobility, and fear of falling in the elderly studied.

The influence of the cannabinoid receptor CB1 on the periaqueductal gray in mice treated with photobiomodulation after chronic constriction injury of the sciatic nerve: a placebo-controlled trial / Influência do receptor canabinóide CB1 na substância cinzenta periaquedutal em camundongos tratados por fotobiomodulação após constrição crônica do nervo ciático: ensaio controlado por placebo

ABSTRACT BACKGROUND AND OBJECTIVES: Studies have demonstrated that the cannabinoid CB1 receptor is involved in the modulation of pain, mainly by activating the descending pain control pathway. However, the role of photobiomodulation in this process is not well elucidated. Thus, the present study aimed to investigate the involvement of the CB1 receptor in the supraspinal photobiomodulation-induced antinociception. METHODS: Male albino swiss mice were submitted to chronic constriction injury and treated with photobiomodulation. To evaluate the supraspinal involvement of the CB1 receptor in the photobiomodulation-induced antinociception, the cannabinoid CB1 receptor antagonist AM251 (0.1µg/vol 0.2µL) was injected 5 minutes before the photobiomodulation treatment. The photobiomodulation treatment was performed on the fifth day after the stereotactic surgery and chronic constriction injury at a dose of 50J/cm2 in acute condition. The hot plate and von Frey monofilaments tests were performed to evaluate the thermal and mechanical pain sensitivity, respectively. RESULTS: The thermal and mechanical nociceptive threshold was higher in mice with chronic constriction injury, injected with saline and treated with photobiomodulation at the dose of 50J/cm2 in both the hot plate (p<0.001) and von Frey (p>0.001) tests. These antinociceptive effects were not detected in mice with chronic constriction injury pre-treated with AM251. CONCLUSION: The present study suggests that CB1 receptors located in Supraspinal structures, participate in the control of neuropathic pain following photobiomodulation treatment in animals undergoing chronic constriction injury.

RESUMO JUSTIFICATIVA E OBJETIVOS: Estudos demonstraram que o receptor canabinóide CB1 está envolvido na modulação da dor, principalmente pela ativação da via descendente de controle da dor, porém o papel da fotobiomodulação nesse processo não é bem elucidado. Assim, o presente estudo teve como objetivo investigar o envolvimento do receptor CB1 na antinocicepção induzida pela fotobiomodulação a nível supraespinhal. MÉTODOS: Camundongos machos suíço albinos foram submetidos à lesão por constrição crônica e tratados com fotobiomodulação. Para avaliar o envolvimento supraespinhal do receptor CB1 na antinocicepção induzida por fotobiomodulação foi injetado o antagonista do receptor canabinóide CB1, AM251 (0,1µg/vol 0,2µL) 5 minutos antes do tratamento com fotobiomodulação. O tratamento de fotobiomodulação foi realizado no quinto dia após cirurgia estereotática e lesão por constrição crônica, na dose de 50J/cm2 em estado agudo. Os testes de placa quente e monofilamentos de von Frey foram realizados para avaliar a sensibilidade térmica e mecânica à dor, respectivamente. RESULTADOS: O limiar térmico e mecânico nociceptivo foi maior nos camundongos com lesão por constrição crônica, injetados com solução salina e tratados com fotobiomodulação na dose de 50J/cm2 nos testes de placa quente (p<0,001) e von Frey (p>0,001). Esses efeitos antinociceptivos não foram detectados em camundongos com lesão por constrição crônica tratados com AM251. CONCLUSÃO: O presente estudo sugere que os receptores CB1 localizados nas estruturas supraespinhais participam do controle da dor neuropática, após tratamento com fotobiomodulação em animais submetidos à lesão por constrição crônica.

Efeito da realidade virtual no recrutamento de fibras musculares e força muscular respiratória em pacientes com doença de Parkinson - estudo piloto / Effect of virtual reality on recruitment of muscle fibers and respiratory muscle strength in patients with Parkinson's disease - pilot study

Introdução: A Doença de Parkinson compromete a mobilidade da caixa torácica, acarretando limitação progressiva da ventilação, devido ao padrão de flexão e rigidez e fraqueza muscular. A realidade virtual propicia interação em tempo real com atividades e ambientes tridimensionais. Objetivo: Avaliar o efeito da realidade virtual no recrutamento de fibras e forças musculares respiratória e postural em pacientes com doença de Parkinson. Métodos: Estudo clínico, piloto, prospectivo, com alocação por conveniência. Dez indivíduos foram selecionados e alocados em grupo estudo (GE n=5) constituídos por idosos com DP e grupo controle (GC n=5) formado por idosos na mesma faixa etária, sem condições clínicas neurológicas e respiratórias. As variáveis mensuradas foram: independência funcional, desempenho motor, força muscular respiratória, recrutamento de fibras musculares respiratórias e posturais, e qualidade de vida. Foram realizadas 16 sessões com realidade virtual. Resultados: As Pressões Inspiratória máxima (PImáx) e Expiratória máxima (PEmáx) melhoraram em alguns momentos da intervenção. O recrutamento de fibras musculares em esternocleidomastóideo diminuiu e o recrutamento de fibras musculares no diafragma aumentou. Conclusão: A PImáx e a PEmáx melhoraram em alguns momentos do tratamento, e houve diminuição do recrutamento de fibras musculares dos músculos respiratórios acessórios nos pacientes com DP. (AU)

Introduction: Parkinson's disease commits the mobility of the rib cage, causing progressive ventilation limitation due to bending and stiffness. Virtual reality provides real-time interaction with activities and three-dimensional environments. Objective: To evaluate the effect of virtual reality on the recruitment of muscle fibers and respiratory and postural muscle strength in patients with Parkinson's disease. Methods: Clinical, pilot, prospective study, with allocation by convenience. Ten individuals were selected and allocated to a study group (EG n = 5) consisting of elderly people with Parkinson and a control group (CG n = 5) formed by elderly people in the same age group, without neurological and respiratory conditions. The measured variables were functional independence, motor performance, respiratory muscle strength, recruitment of respiratory and postural muscle fibers, and quality of life. 16 sessions were held with virtual reality. Results: The maximum inspiratory pressures (MIP) and maximum expiratory pressures (MEP) improved in some moments of the intervention. The recruitment of muscle fibers in the sternocleidomastoid decreased and the recruitment of muscle fibers in the diaphragm increased. Conclusion: MIP and MEP improved in some moments of treatment, and there was a decrease in the recruitment of muscle fibers from accessory respiratory muscles in patients with PD. (AU)

Doença de Parkinson: efeito da terapia vibratória no recrutamento da musculatura postural / Parkinson disease: effects of vibrating therapy in recruitment of postural muscle

A Doença de Parkinson (DP) é uma doença degenerativa e progressiva do sistema nervoso central, caracterizada por sintomas motores, alterações musculoesqueléticas e posturais que podem ser influenciadas por um processo de organização sensorial anormal. A eletromiografia (EMG) é uma ferramenta de avaliação não invasiva importante para análise do recrutamento da musculatura postural. A terapia vibratória surge como uma opção promissora na estimulação somatossensorial desta população. Objetivo: Avaliar os efeitos da terapia vibratória no recrutamento da musculatura postural em pacientes com DP. Métodos: Foram analisados os músculos longuíssimo lombar (LL) e trapézio ascendente (TA) por EMG. Foi realizada a aplicação de um protocolo de 8 semanas (24 atendimentos) de terapia vibratória em 10 indivíduos com DP, com avaliação e reavaliação por análise eletromiográfica da contração isométrica voluntária (CIV). Resultados: A terapia vibratória não mostrou resultados significativos na ativação da musculatura postural na DP, pela avaliação por EMG, sendo na comparação pré e pós-tratamento TAD (p = 0,655), TAE (p = 0,655), LLD (p = 0,848) e LLE (p = 0,565). Conclusão: Não houve resultados significativos na EMG após intervenção com terapia vibratória em indivíduos com DP, o que pode ser devido principalmente ao tamanho amostral. Sugere-se a realização de novos estudos com maior tamanho amostral para comprovar a eficiência da terapia vibratória nesta população.

Parkinson Disease (PD) is a degenerative and progressive disease of the central nervous system, characterized by motor symptoms, musculoskeletal and postural disturbance, which may be influenced by an abnormal sensory organization process. Electromyography (EMG) is an important non-invasive assessment tool for postural muscle recruitment analysis. Vibratory therapy appears as promising option to somatosensory stimulation in this population. Objective: To evaluate the effects of vibratory therapy on the recruitment of postural muscles in patients with PD. Methods: Longissimus lumborum (LL) and the upper trapezius (UT) muscles were analyzed by EMG. A protocol of 8 weeks (24 attendances) of vibratory therapy was applied in 10 individuals with PD, with evaluation and revaluation performed by EMG analysis of voluntary isometric contraction (VIC). Results: Vibratory therapy did not show significant results in the activation of the postural muscles in the PD, by the EMG evaluation, being the TAD (p = 0.655), APR (p = 0.655), LLD (p = 0.848) and LLE (p = 0.565). Conclusion: We did not observe significant results in the EMG after intervention with vibratory therapy in individuals with PD, which may be mainly due to the sample size. It is suggested to carry out new studies with a larger sample size to prove the efficiency of the vibratory therapy in this population.

Laserpuntura na neuropatia periférica: efeitos na dor e qualidade de vida / Laserpuncture in peripheral neuropathy: effects on pain and quality of life

Introdução: A laserpuntura é utilizada para analgesia, embora os protocolos para aplicação na dor neuropática permaneçam contraditórios. Objetivo: Avaliar o efeito da laserpuntura na modulação da dor neuropática, impacto na qualidade de vida e processo inflamatório local. Material e métodos: Cinco pacientes com diagnóstico de lesão nervosa periférica e dor neuropática associada receberam aplicação do laser AlGaInP, 658 nm, 10 mW, 9 J/cm2, em acupontos especí­ficos, durante 15 sessões, 3 vezes na semana, por 50 minutos. A avaliação pré e pós-intervenção foi realizada pela Escala Visual Analógica, questionário para dor (McGill), questionário de qualidade de vida (SF-36), Índice de incapacidade de Oswestry e termografia. Resultados: Foi observada redução da média da pontuação na Escala Visual Analógica em 3 de 5 pacientes e redução da média de dor após 15 sessões. A avaliação pelo McGill mostrou redução nas dimensões afetivo, avaliativo e total. No questionário SF-36 foi observada melhora das dimensões Capacidade Funcional e Limitação por Aspectos Emocionais. No Índice de Oswestry observou-se redução da média da porcentagem e na termografia não houve diferença nos valores pré e pós-intervenção. Conclusão: Estes resultados sugerem eficácia da laserpuntura na redução da dor e melhora da qualidade de vida em pacientes com dor neuropática decorrente de lesão nervosa periférica. (AU)

Introduction: Laserpuncture is used for analgesia, although the protocols for use in neuropathic pain remain contradictory. Objective: To evaluate the effect of laserpuncture in modulating neuropathic pain, impact on quality of life and local inflammatory process. Methods: Five patients with peripheral nerve injury and neuropathic pain associated application received AlGaInP laser, 658 nm, 10 mW, 9 J/cm2 at specific acupoints for 15 sessions, 3 times a week for 50 minutes. The pre- and post-intervention were performed by Visual Analogue Scale, questionnaire for pain (McGill), quality of life questionnaire (SF-36), Oswestry disability index and thermography. Results: A significant reduction in Visual Analogue Scale score average was observed in 3 of 5 patients in addition to an overall reduction of average pain after 15 sessions. The evaluation by McGill showed reduction in affective, evaluative and overall dimensions. In the SF-36 questionnaire was observed an increase of the dimensions Functional Capacity and Emotional Aspects. In Oswestry Index a reduction was observed in the average percentage and in the thermography no difference was noticed in pre and post-intervention. Conclusion: These results suggest effectiveness of laser acupuncture in reducing pain and improving quality of life in patients with neuropathic pain due to peripheral nerve injury. (AU)