title: Histological, histochemical, and protein changes after induced malocclusion by occlusion alteration of Wistar rats.
abstract: Although disorders of the stomatognathic system are common, the mechanisms involved are unknown. Our objective was to study the changes in the masseter muscles after unilateral exodontia. Molar extraction was performed on Wistar rats (left side), and the animals were sacrificed after either 14 or 26 days. The masseter muscle was processed for histological analysis, conventional and in situ zymography, and immunohistochemistry. The morphological analysis showed unique and specific characteristics for the experimental group. By conventional zymography no significant values of 72 kDa MMP-2 (P < 0.05) were found in both of the sides of masseter muscle after 14 and 26 days of unilateral extraction. The in situ zymography showed gelatinolytic activity on all deep masseter muscles, with significant increase on the contralateral side after 14 and 26 days (P < 0.05). The immunohistochemistry demonstrated greater expression of MMP-2 than MMP-9 and MMP-14 in all masseter muscles and there were few differences in the staining of 4 TIMPs. This knowledge about morphology and molecular masticatory muscle remodeling following environmental interventions can be used to develop clinically successful treatments.
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: Carolina de Souza
authors.initials: Cde S
authors.lastname: Guerra
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: Yamba
authors.initials: Y
authors.lastname: Carla Lara Pereira
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: João Paulo Mardegan
authors.initials: JP
authors.lastname: Issa
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: Kelly Galisteu
authors.identifier: 0000-0002-6249-5518
authors.initials: KG
authors.lastname: Luiz
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: Elaine A Del Bel
authors.initials: EA
authors.lastname: Guimarães
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: Raquel Fernanda
authors.initials: RF
authors.lastname: Gerlach
authors.affiliation: Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo, FORP/USP, P.O. Box 14040-904, Ribeirao Preto, SP, Brazil.
authors.forename: Mamie Mizusaki
authors.initials: MM
authors.lastname: Iyomasa
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D008297:Male; D008310:Malocclusion / Q000378:metabolism* / Q000473:pathology; D008406:Masseter Muscle / Q000378:metabolism* / Q000473:pathology; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism*; D011817:Rabbits; D017208:Rats, Wistar; D019714:Tissue Inhibitor of Metalloproteinases / Q000378:metabolism*
chemical_list: D009124:Muscle Proteins; D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases