title: Menopause, exercise, and knee. What happens?
abstract: OBJECTIVE
  To check if ovariectomy produces alterations in the articular cartilage structure of the tibial proximal epiphysis and if aerobic physical exercise has any influence on these alterations.
  
  
  METHODS
  Six-month-old female Wistar rats were distributed in three groups: Control group (CG), without ovariectomy and physical activity; Oophorectomy and sedentary group (OSG), with bilateral ovariectomy and without physical activity, and Oophorectomy and trained group (OTG), with bilateral ovariectomy and physical activity during 3 months. All rats were euthanised at 9 months of age. The results were obtained by using histological sections stained with Hematoxylin and Eosin, and Picrosirius stain.
  
  
  RESULTS
  In relation to the thickness of the articular cartilage an increase was observed in the superficial layer in OSG in relation to OTG. The number of chondrocytes did not show any significant difference. The nuclear volume of chondrocytes in the superficial layer was higher in CG than in OSG . In the medium layer, the volume of chondrocytes was higher in CG than in OSG and the OTG. The same occurred when the values of the epiphysial cartilage was considered as a whole. For the collagen, the values of volume density of the collagen fibers were higher in the OSG and in the OTG than the CG. The same occurred with the OTG in relation to OSG.
  
  
  CONCLUSIONS
  The depression of estrogen levels produced important changes in the tibial cartilage of Wistar rats mainly on the superficial layer and physical activity seemed to relieve these effects.
authors: Department of Surgery, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil. renata.fontenele@globo.com
authors: Renata Gabriel
authors: RG
authors: Fontinele
authors: Valquiria Barboza
authors: VB
authors: Mariotti
authors: Amanda Messias
authors: AM
authors: Vazzoleré
authors: Juliana Shimara Pires
authors: JS
authors: Ferrão
authors: José Roberto
authors: JR
authors: Kfoury
authors: Romeu Rodrigues
authors: RR
authors: De Souza
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism*; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D007719:Knee Joint; D008593:Menopause / Q000378:metabolism*; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003094:Collagen