RESUMO
BACKGROUND: In this study, we evaluate the role of RGMa (Repulsive Guidance Molecule a) during peripheral nerve regeneration using the mouse median nerve model. METHODS: By real-time PCR and Western Blot analysis, we examined expression changes of RGMa mRNA and RGMa protein in neural tissue after transection and microsurgical repair of the mouse median nerve distal to the transection site. We evaluated histomorphometrical changes in neural tissue distal to the injury site and functional recovery of the grasping force after median nerve transection and repair in wild-type mice and RGMa+/- heterozygous mice. RESULTS: RT-PCR revealed a 1,8 fold increase of RGMa mRNA two weeks and a 4,4 fold increase of RGMa mRNA 3 weeks after nerve transection and repair in the nerve segment distal to the injury site. In Western blot analysis, we could show a high increase of RGMa in the nerve segment distal to the injury site at day 14. Histomorphometrical analysis showed significant differences between wild-type animals and heterozygous animals. The absolute number of myelinated fibres was significantly higher in operated heterozygous RGMa+/- animals compared to operated wildtye animals. Using the functional grasping test, we could demonstrate that peripheral nerve regeneration is significantly diminished in heterozygous RGMa+/- mice. CONCLUSIONS: Employing the mouse median nerve model in transgenic animals, we demonstrate that RGMa plays an important role during peripheral nerve regeneration.
Assuntos
Proteínas Ligadas por GPI/fisiologia , Nervo Mediano/lesões , Nervo Mediano/fisiopatologia , Atividade Motora/fisiologia , Regeneração Nervosa/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Traumatismos dos Nervos Periféricos/metabolismo , Animais , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Proteínas Ligadas por GPI/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: Less is known about the role of Netrin-1 in the peripheral nervous system. In this study, we evaluated the role of Netrin-1 using the mouse median nerve model for assessment of peripheral nerve regeneration. METHODS: Using real-time PCR and western blot analysis, we examined expression changes of netrin-1 mRNA and Netrin-1 protein after transection and repair of the mouse median nerve in Wild-type animals. We further evaluated histomorphometrical changes as well as the functional recovery of the grasping force after median nerve transection and repair in WT mice and Netrin-1(+/-) heterozygous mice. RESULTS: RT-PCR revealed a 1, 9 fold increase of Netrin-1 mRNA two weeks after nerve transection and repair in the nerve segment distal to the injury site. In Western blot analysis, we could show a high increase of Netrin-1 in the nerve segment distal to the injury site at day 14. Histomorphometrical analysis showed significantly higher cross sectional area and a lower fibre density in heterozygous Netrin-1(+/-) mice. Using the functional grasping test, we could show that peripheral nerve regeneration is significantly diminished in heterozygous Netrin-1(+/-) mice. CONCLUSIONS: Employing the mouse median nerve model in transgenic animals, we demonstrate that Netrin-1 plays an important role during peripheral nerve regeneration.
