Brazil. Conception, design and scientific content of the study, critical revision. ABSTRACT PURPOSE:To evaluate the capacity of natural latex membrane to accelerate and improve the regeneration quality of the of rat sciatic nerves. METHODS:Forty male adult Wistar rats were used, anesthetized and operated to cut the sciatic nerve and receive an autograft or a conduit made with a membrane derived from natural latex (Hevea brasiliensis). Four or eight weeks after surgery, to investigate motor nerve recovery, we analyzed the neurological function by walking pattern (footprints analysis and computerized treadmill), electrophysiological evaluation and histological analysis of regenerated nerve (autologous nerve graft or tissue cables between the nerve stumps), and anterior tibial and gastrocnemius muscles. RESULTS:All functional and morphological analysis showed that the rats transplanted with latex conduit had a better neurological recovery than those operated with autologous nerve: quality of footprints, performance on treadmill (p<0.01), electrophysiological response (p<0.05), and quality of histological aspects on neural regeneration. CONCLUSION:The data reported showed behavioral and functional recovery in rats implanted with latex conduit for sciatic nerve repair, supporting a complete morphological and physiological regeneration of the nerve. -Acta Cirúrgica Brasileira -Vol. 27 (12) 2012ciático seccionado de ratos. MÉTODOS:Foram utilizados 40 ratos machos adultos da linhagem Wistar, anestesiados e operados com autoenxerto ou com interposição de um tubo confeccionado com uma membrana derivada do latex natural (Havea brasiliensis). Quatro ou oito semanas após a cirurgia, para investigar a recuperação motora do nervo, foram analisadas a função neurológica através do padrão da marcha (análise das pegadas e esteira computadorizada), avaliação eletrofisiológica e análise histológica do nervo regenerado (enxerto de nervo autólogo ou formação de nervo novo entre os cotos nervosos) e músculos gastrocnêmio e tibial anterior. RESULTADOS:Todas as análises morfológicas e funcionais demonstraram que os ratos transplantados com o conduto de látex tiveram recuperação melhor do que aqueles operados com nervo autólogo: qualidade das pegadas impressas, desempenho em esteira (p<0,01), resposta eletrofisiológica (p<0,05), e qualidade histológica da regeneração nervosa. CONCLUSÃO:Os dados apresentados demonstraram recuperação comportamental e funcional nos ratos implantados com o conduto de látex para a reparação do nervo ciático por meio de uma completa regeneração morfológica e fisiológica do nervo.Descritores: Regeneração Nervosa. Látex. Engenharia Tecidual. Ratos.

A membrane produced from a natural latex has been used successfully both experimentally (angioplasties, esophagus neoformation, reconstruction of the ocular conjuntive) and clinically (myringoplasties, treatment of skin ulcers), demonstrating angiogenic potential and leading to tissue neoformation. We evaluated the ability of this natural latex membrane in speeding up and improve the regeneration of sectioned sciatic nerve in rats. Forty adult male Wistar rats were divided in 4 experimental groups (n=10 each) and operated with the auto‐scion or the interposition of a tube made up of that membrane derived from natural latex (Hevea Brasiliensis). After 4 or 8 weeks, animals were submitted to neurological function evaluation, pace evaluation and electromyography. Afterwards, the animals were killed and the nerves were processed for paraffin embedding and observation under light microscopy. Our results indicated that the rats operated with latex have a better recovery rate than the ones operated with autologous nerve duo to the higher use rates of the operated paw. Morphologically, the regenerative capacity of the latex membrane is larger than auto‐scion of the sciatic nerve in rats.Grant Funding Source : FAPESP, CNPq and FAEPA

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