title: Effects of microcurrent therapy on excisional elastic cartilage defects in young rats.
abstract: The effects of microcurrent application on the elastic cartilage defects in the outer ear of young animals were analyzed. Sixty male Wistar rats were divided into a control (CG) and a treated group (TG). An excisional lesion was created in the right outer ear of each animal. Daily treatment was started after 24h and consisted of the application of a low-intensity (20μA) continuous electrical current to the site of injury for 5min. The animals were euthanized after 7, 14 and 28 days of injury and the samples were submitted to analyses. In CG, areas of newly formed cartilage and intense basophilia were seen at 28 days, while in TG the same observations were made already at 14 days. The percentage of birefringent collagen fibers was higher in CG at 28 days. The number of connective tissue cells and granulocytes was significantly higher in TG. Ultrastructural analysis revealed the presence of chondrocytes in TG at 14 days, while these cells were observed in CG only at 28 days. Cuprolinic blue staining and the amount of glycosaminoglycans were significantly higher in TG at 14 days and 28 days. The amount of hydroxyproline was significantly higher in TG at all time points studied. The active isoform of MMP-2 was higher activity in TG at 14 days. Immunoblotting for type II collagen and decorin was positive in both groups and at all time points. The treatment stimulated the proliferation and differentiation of connective tissue cells, the deposition of glycosaminoglycans and collagen, and the structural reorganization of these elements during elastic cartilage repair.
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil.
authors.forename: Edson Pereira
authors.initials: EP
authors.lastname: Tangerino Filho
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Fachi
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil.
authors.forename: Israel Costa
authors.initials: IC
authors.lastname: Vasconcelos
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil.
authors.forename: Glaucia Maria Tech
authors.initials: GM
authors.lastname: Dos Santos
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil.
authors.forename: Fernanda Aparecida Sampaio
authors.initials: FA
authors.lastname: Mendonça
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil.
authors.forename: Andrea Aparecida
authors.initials: AA
authors.lastname: de Aro
authors.affiliation: Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, Rua Charles Darwin, s/n. CxP 6109, 13083-863 Campinas, SP, Brazil.
authors.forename: Edson Rosa
authors.initials: ER
authors.lastname: Pimentel
authors.affiliation: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av. Dr. Maximiliano Baruto, 500 Jd. Universitário, 13607-339 Araras, SP, Brazil. Electronic address: marcelosquisatto@uniararas.br.
authors.forename: Marcelo Augusto Marretto
authors.initials: MA
authors.lastname: Esquisatto
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000254:growth & development / Q000528:radiation effects; D002454:Cell Differentiation / Q000528:radiation effects*; D049109:Cell Proliferation / Q000528:radiation effects*; D019902:Chondrocytes / Q000528:radiation effects; D003094:Collagen / Q000378:metabolism; D004431:Ear, External / Q000254:growth & development / Q000293:injuries / Q000528:radiation effects*; D051472:Elastic Cartilage / Q000254:growth & development / Q000528:radiation effects*; D060733:Electromagnetic Radiation; D008297:Male; D051381:Rats; D014945:Wound Healing / Q000528:radiation effects
chemical_list: D003094:Collagen
keywords: Collagen; Electrotherapy; Glycosaminoglycans; MMP; Tissue repair