RESUMO
INTRODUCTION: Severe lesions in the facial nerve may have extensive axonal loss and leave isolated stumps that impose technical difficulties for nerve grafting. METHODS: We evaluated bone marrow stem cells (BMSC) in a silicone conduit for rat facial nerve regeneration from isolated stumps. Group A utilized empty silicone tubes; in groups B-D, the tube was filled with acellular gel; and, in groups C and D, undifferentiated BMSC (uBMSC) or Schwann-like cells differentiated from BMSC (dBMSC) were added, respectively. Compound muscle action potentials (CMAPs) were measured, and histology was evaluated. RESULTS: Groups C and D had the highest CMAP amplitudes. Group C had shorter CMAP durations than groups A, B, and D. Distal axonal number and density were increased in group C compared with groups A and B. CONCLUSIONS: Regeneration of the facial nerve was improved by both uBMSC and dBMSC in rats, yet uBMSC was associated with superior functional results.
Assuntos
Cotos de Amputação/cirurgia , Transplante de Medula Óssea/métodos , Nervo Facial/citologia , Células-Tronco Mesenquimais/fisiologia , Músculo Esquelético/fisiopatologia , Regeneração Nervosa/fisiologia , Potenciais de Ação/fisiologia , Animais , Axônios/patologia , Células Cultivadas , Eletromiografia , Seguimentos , Masculino , Fator 6 de Transcrição de Octâmero/metabolismo , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Receptor de Fator de Crescimento Neural/metabolismo , Proteínas S100/metabolismo , Estatísticas não Paramétricas , Transdução Genética , beta-Galactosidase/genética , beta-Galactosidase/metabolismoRESUMO
BACKGROUND: Nerve repair with fibrin glue is an alternative to conventional suture technique, although there is no definitive experimental evaluation of the 2 techniques. This experimental study was undertaken to evaluate nerve regeneration after sciatic nerve repair with fibrin glue and to compare it with repair performed with suture and a combination of both techniques. METHODS: Eighty-six male Wistar rats were subjected to right sciatic nerve transection and immediate repair with 4-stitch nylon suture (group A), fibrin glue (group B), or a combination of both techniques (group C). Walking track analysis to access functional recovery was performed preoperatively and 12 weeks postoperatively. Before nerve section and after a 24-week interval, the nerve and motor action potentials (MAPs) were evaluated. Histomorphometric evaluation was carried out 24 weeks after nerve section. Differences between groups were evaluated for significance using the Kruskal-Wallis or analysis of variance methods. RESULTS: Animals of group B presented better results than those of group A when the functional evaluation was applied (P < .05). When nerve conduction velocity was evaluated at reoperation and the ratio between conduction velocity at reoperation and before the nerve section in MAP evaluation were measured and compared in the 3 groups, the rats of group B presented better results than those of group A (P < .05). Animals of group C presented better results than those of group A when the ratio between nerve conduction velocities was considered. There was no difference between the nerve repair methods when histomorphometric evaluation was performed. CONCLUSION: In a rat model, nerve repair using fibrin glue provided better conditions for regeneration than suture after sciatic nerve transection.
Assuntos
Adesivo Tecidual de Fibrina/farmacologia , Regeneração Nervosa/fisiologia , Procedimentos Neurocirúrgicos/métodos , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/cirurgia , Neuropatia Ciática/cirurgia , Técnicas de Sutura/estatística & dados numéricos , Potenciais de Ação/fisiologia , Animais , Modelos Animais de Doenças , Adesivo Tecidual de Fibrina/uso terapêutico , Transtornos Neurológicos da Marcha/tratamento farmacológico , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/cirurgia , Membro Posterior/inervação , Membro Posterior/fisiopatologia , Locomoção/fisiologia , Masculino , Regeneração Nervosa/efeitos dos fármacos , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Nervo Isquiático/fisiologia , Neuropatia Ciática/tratamento farmacológico , Neuropatia Ciática/fisiopatologia , Suturas/estatística & dados numéricos , Resultado do TratamentoRESUMO
Ao contrário da grande capacidade de regeneraçäo observada em nervos periféricos, a do tecido nervoso central adulto é mínima após trauma. Apesar dos rearranjos sinápticos subseqüentes ao trauma, lesoes medulares resultam em déficits permanentes. Intervençöes no micro-ambiente neuronal säo necessárias para promover regeneraçäo e proteçäo de neurônios medulares lesados.
Assuntos
Humanos , Regeneração Nervosa , Traumatismos da Medula Espinal/reabilitaçãoRESUMO
The marker horseradish peroxidase (HRP) was used to retrogradely label the cell bodies of origin of the nerve fibers responsible for thymic innervation. The thymus was exposed in albino rats under general anesthesia and a conjugate of HRP-WGA was injected bilaterally into the gland parenchyma. After a survival time of 3 days, the animals were anesthetized and perfused transcardially. Their brainstems were removed and serially sectioned and together with the whole sympathetic chains were processed for HRP demonstration. Labeled cell bodies were identified in the brainstem at the level of the retrofacial and ambiguous nuclei bilaterally. In the sympathetic chain, labeled neurons were present from the first cervical to the ninth thoracic ganglion, although they were detected in higher numbers in the superior cervical and stelate ganglia.
