Ultrastructural study of the effects of cyclosporine in the brainstem of Wistar rats submitted to the ethidium bromide demyelinating model.
The ethidium bromide-demyelinating model (EB) was used to study remyelination in the brainstem under the use of cyclosporine (CsA). Wistar rats were submitted to intracisternal injection of 0.1% EB or 0.9% saline solution, and others were taken as histologic controls (group I). Within those injected with EB, some have not received immunosuppressive treatment (II); some were treated by intraperitonial route with CsA (III.E-10 mg/kg/day). Rats from group III.C were injected with saline solution and treated with CsA. The animals were perfused from 15 to 31 days post-injection collecting brainstem sections for light and transmission electron microscopy studies. After EB injection it was noted the presence of macrophages and non-degraded myelin debris, demyelinated axons, oligodendrocyte or Schwann cell remyelinated axons, groups of infiltrating pial cells, hypertrophic astrocytes and few lymphocytes. Tissue repair of EB-induced lesions in group III.E was similar to that of group II, but with the presence of a higher density of oligodendrocytes near remyelinating areas.
Bondan
Eduardo Fernandes
EF
Universidade Paulista, São Paulo, SP, Brazil. bondan@uol.com.br
Lallo
Maria Anete
MA
Graça
Dominguita Lühers
DL
D000818:Animals; D001933:Brain Stem / Q000166:cytology / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D016572:Cyclosporine / Q000627:therapeutic use*; D003711:Demyelinating Diseases / Q000139:chemically induced / Q000188:drug therapy / Q000473:pathology* / Q000503:physiopathology; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D004996:Ethidium; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008264:Macrophages / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D046529:Microscopy, Electron, Transmission; D009186:Myelin Sheath / Q000187:drug effects / Q000502:physiology; D009457:Neuroglia / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure*; D009836:Oligodendroglia / Q000187:drug effects / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000187:drug effects / Q000648:ultrastructure
D007166:Immunosuppressive Agents; D016572:Cyclosporine; D004996:Ethidium