Analysis of collagenous matrix of bones from intramembranous and endochondral origin of young and aged rats

• Grant number: 16/16806-2
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): April 01, 2017
• Effective date (End): September 30, 2019
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal Investigator: Mariza Akemi Matsumoto
• Grantee: Ana Carolina Zucon Bacelar
• Home Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Knowledge about biological mechanisms and responses of human skeleton in face of several local and systemic conditions are mostly due to the in vivo studies using animal models, particularly the small rodents for their easy handling, resistance and known genetics. Since they are short-term life animals, the rhythm of metabolism, growing, and bone maturing are substantially different from human beings, turning age equivalence between species a difficult task, as well as study suitability to skeletal condition of the animal considering its age. In this way, the present study aims to analyze intramembranous and endochondral bones of rats in different development stages, with emphasis to the collagenous matrix considering its essential role on bone tissue mineralization, which consequently reflects on its mechanical properties. Forty male Wistar rats, 6, 12, 18, and 24 months of age, will compound four groups with 10 animals each. They will be euthanized in order to permit removal of the calvaria, mandibular, and femur bones. The bones will undergo histotechnical procedures for the confectioning of the histological slices stained with H.E. and Goldner trichrome for microscopic morphological analysis of cortical and trabecular areas, study of mature and immature bone, reversal lines, osteoclastic and/or osteoblastic activity, as well as the characteristics of medullar tissue. Slices stained with Picrosirius-Red will be analyzed in order to qualify collagenous matrix of the bones using polarized light microscopy. Collagenous matrix will be also analyzed under immunohistochemistry analysis, using anti-colagen type I and anti-pentosidine antibodies. (AU)