title: Ethidium bromide-induced demyelination in the sciatic nerve of diabetic rats.
abstract: This study aims to observe the process of myelin loss and repair following the injection of the gliotoxic agent ethidium bromide (EB) in the sciatic nerve of rats previously induced to diabetes mellitus by streptozotocin. Injection of EB was also done in non-diabetic rats. The animals were euthanatized from 3 to 31 days after intraneural injection and nerve sections were collected for ultrastructural study. In non-diabetic rats, Schwann cells (CS) showed signs of intoxication 3 days after, with cytoplasmic vacuolization and rejection of their myelin sheaths. Myelin debris were removed by macrophages in the endoneurium and mast cells were abundant in the lesions. From 14 days following EB injection, supernumerary CS were seen in the expanded endoneurium as well as thin myelin sheaths indicating remyelination. Diabetic rats presented a more extensive myelin vesiculation and segmentar demyelination, with delayed activities from both macrophages and remyelinating SC. No mast cells were noted.
authors.affiliation: Universidade Paulista, São Paulo, SP, Brasil. bondan@uol.com.br
authors.forename: Eduardo Fernandes
authors.initials: EF
authors.lastname: Bondan
authors.forename: Paulo Ruggiero
authors.initials: PR
authors.lastname: Custódio
authors.forename: Maria Anete
authors.initials: MA
authors.lastname: Lallo
authors.forename: Henri Donnarumma Levy
authors.initials: HD
authors.lastname: Bentubo
authors.forename: Dominguita Luhers
authors.initials: DL
authors.lastname: Graça
mesh_terms: D000818:Animals; D003711:Demyelinating Diseases / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology; D004996:Ethidium / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000187:drug effects* / Q000648:ultrastructure; D012584:Sciatic Nerve / Q000187:drug effects* / Q000648:ultrastructure; D013311:Streptozocin
chemical_list: D013311:Streptozocin; D004996:Ethidium