Protocol on induction of TMJ articular disc degeneration in rats by utilization of botulinum toxin.
OBJECTIVE
To develop a model of experimental degeneration in the articular disc of the TMJ of rats through the use of botulinum toxin that can be used in future studies of degenerative diseases on fibrocartilage.


METHODS
Aiming at the above-mentioned objective, 12 Lewis male rats were used and divided into two groups: CG, control group and DG, group of animals to which the botulinum toxin was administered (6 units/kg). The morphological analysis was carried out utilizing histological cuts stained with hematoxyline-eosine, toluidine blue and Picrosirius; the biochemical analysis was made by SDS-polyacrylamide gel electrophoresis.


RESULTS
The DG showed peculiar characteristics regarding a degeneration joint disk, compatible with those described in literature as: reduction of cells number, general disorganization of cells direction and extracellular matrix, increase in glycosaminoglycans content and degradation of the tissue collagen.


CONCLUSIONS
Based on the morphological and biochemical results, it was concluded that the proposed degeneration model showed to be satisfactory for futures studies of injuries and fibrocartilage regeneration processes.
Da Ré Guerra
Flávia
F
Department of Anatomy, Cell Biology and Physiology and Biophysics, Institute of Biology, UNICAMP, Campinas, SP, Brazil. dgflavia@yahoo.com.br <dgflavia@yahoo.com.br>
de Souza Pires
Ivan Luiz
IL
de Aro
Andrea Aparecida
AA
Camargo
Lilian Calili
LC
Pimentel
Edson Rosa
ER
Palomari
Evanisi Teresa
ET
D000818:Animals; D001284:Atrophy; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000009:adverse effects*; D002357:Cartilage Diseases / Q000139:chemically induced*; D002452:Cell Count; D024042:Collagen Type I / Q000187:drug effects; D004396:Coloring Agents; D004195:Disease Models, Animal; D004591:Electrophoresis, Polyacrylamide Gel; D005109:Extracellular Matrix / Q000187:drug effects; D016326:Extracellular Matrix Proteins / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects / Q000473:pathology; D051445:Fibrocartilage / Q000187:drug effects; D000071235:Fibromodulin; D005456:Fluorescent Dyes; D006025:Glycosaminoglycans / Q000032:analysis; D007273:Injections, Intramuscular; D008297:Male; D008406:Masseter Muscle / Q000187:drug effects; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000009:adverse effects*; D011509:Proteoglycans / Q000187:drug effects; D051381:Rats; D011917:Rats, Inbred Lew; D019224:Temporomandibular Joint Disc / Q000187:drug effects*; D013705:Temporomandibular Joint Disorders / Q000139:chemically induced*
D024042:Collagen Type I; D004396:Coloring Agents; D016326:Extracellular Matrix Proteins; D005456:Fluorescent Dyes; C000604334:Fmod protein, rat; D006025:Glycosaminoglycans; D009465:Neuromuscular Agents; D011509:Proteoglycans; D000071235:Fibromodulin; D019274:Botulinum Toxins, Type A