Phrenic nerve diabetic neuropathy in rats: unmyelinated fibers morphometry

Autor(es)

Fazan, Valeria Paula S. ^{[1, 2]} ; Rodrigues Filho, Omar A. ^[3] ; Jordao, Caroline E. R. ^[2] ; Moore, Kenneth C. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Iowa, Cent Microscopy Res Facil, Iowa City, IA - USA

^[2] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Surg & Anat, BR-14049900 Ribeirao Preto - Brazil

^[3] Univ Fed Triangulo Mineiro, Dept Biol Sci, Uberaba, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM; v. 14, n. 2, p. 137-145, JUN 2009.
• Citações Web of Science: 12

Resumo

We have demonstrated that phrenic nerves' large myelinated fibers in streptozotocin (STZ)-induced diabetic rats show axonal atrophy, which is reversed by insulin treatment. However, studies on structural abnormalities of the small myelinated and the unmyelinated fibers in the STZ-model of neuropathy are limited. Also, structural changes in the endoneural vasculature are not clearly described in this model and require detailed study. We have undertaken morphometric studies of the phrenic nerve in insulin-treated and untreated STZ-diabetic rats and non-diabetic control animals over a 12-week period. The presence of neuropathy was assessed by means of transmission electron microscopy, and morphometry of the unmyelinated fibers was performed. The most striking finding was the morphological evidence of small myelinated fiber neuropathy due to the STZ injection, which was not protected or reversed by conventional insulin treatment. This neuropathy was clearly associated with severe damage of the endoneural vessels present on both STZ groups, besides the insulin treatment. The STZ-diabetes model is widely used to investigate experimental diabetic neuropathies, but few studies have performed a detailed assessment of either unmyelinated fibers or capillary morphology in this animal model. The present study adds useful information for further investigations on the ultrastructural basis of nerve function in diabetes. (AU)

• Processo FAPESP: 06/06362-8 - Avaliação morfológica ultraestrutural das alterações do nervo renal de ratos diabéticos induzidos experimentalmente
• Beneficiário: Valéria Paula Sassoli Fazan
• Modalidade de apoio: Bolsas no Exterior - Pesquisa
• Processo FAPESP: 04/09139-2 - Estudos morfofuncionais e morfométricos do sistema nervoso central e periférico e do sistema cardiovascular, envolvidos na regulação neuro-humoral de funções neurovegetativas e comportamentais
• Beneficiário: Helio Cesar Salgado
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 07/08498-7 - Avaliação em nível de microscopia eletrônica de transmissão do nervo frênico de ratos diabéticos crônicos induzidos experimentalmente
• Beneficiário: Caroline Echavarria Rodrigues Jordão
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 06/03200-7 - Estudo morfológico e morfométrico do nervo sural de ratos normotensos, espontaneamente hipertensos (SHR) e espontaneamente hipertensos com diabete induzido experimentalmente
• Beneficiário: Valéria Paula Sassoli Fazan
• Modalidade de apoio: Auxílio à Pesquisa - Regular