title: Effects of microcurrent stimulation on hyaline cartilage repair in immature male rats (Rattus norvegicus).
abstract: BACKGROUND
  In this study, we investigate the effects of microcurrent stimulation on the repair process of xiphoid cartilage in 45-days-old rats.
  
  
  METHODS
  Twenty male rats were divided into a control group and a treated group. A 3-mm defect was then created with a punch in anesthetized animals. In the treated group, animals were submitted to daily applications of a biphasic square pulse microgalvanic continuous electrical current during 5 min. In each application, it was used a frequency of 0.3 Hz and intensity of 20 μA. The animals were sacrificed at 7, 21 and 35 days after injury for structural analysis.
  
  
  RESULTS
  Basophilia increased gradually in control animals during the experimental period. In treated animals, newly formed cartilage was observed on days 21 and 35. No statistically significant differences in birefringent collagen fibers were seen between groups at any of the time points. Treated animals presented a statistically larger number of chondroblasts. Calcification points were observed in treated animals on day 35. Ultrastructural analysis revealed differences in cell and matrix characteristics between the two groups. Chondrocyte-like cells were seen in control animals only after 35 days, whereas they were present in treated animals as early as by day 21. The number of cuprolinic blue-stained proteoglycans was statistically higher in treated animals on days 21 and 35.
  
  
  CONCLUSIONS
  We conclude that microcurrent stimulation accelerates the cartilage repair in non-articular site from prepuberal animals.
authors: Programa de Pós-graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, Av, Dr, Maximiliano Baruto, 500 Jd, Universitário, 13607-339, Araras, SP, Brazil.
authors: Carla
authors: C
authors: de Campos Ciccone
authors: Denise Cristina
authors: DC
authors: Zuzzi
authors: Lia Mara Grosso
authors: LM
authors: Neves
authors: Josué Sampaio
authors: JS
authors: Mendonça
authors: Paulo Pinto
authors: PP
authors: Joazeiro
authors: Marcelo Augusto Marretto
authors: MA
authors: Esquisatto
mesh_terms: D000818:Animals; D001491:Basophils / Q000378:metabolism; D002113:Calcification, Physiologic; D019902:Chondrocytes / Q000378:metabolism*; D004558:Electric Stimulation; D004599:Electric Stimulation Therapy; D051457:Hyaline Cartilage / Q000378:metabolism* / Q000648:ultrastructure; D008297:Male; D011509:Proteoglycans / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014945:Wound Healing; D014947:Wounds and Injuries / Q000378:metabolism / Q000628:therapy*
chemical_list: D011509:Proteoglycans