title: [Expression of mRNA of osteocalcin in condylar cartilage of young SD rats after functional protrusion].
abstract: OBJECTIVE
  To study the temporal and spatial patterns of the expression of mRNA in condylar cartilage of young growing SD rats, in condition of different functional treatment time span.
  
  
  METHODS
  SD rats are randomly divided into 3 groups: control, all-day group (wearing functional appliance for 24 hours a day) and 12-hour group (wearing appliance for 12 hours in daytime). After one week, animals are sacrificed and Osteocalcin mRNA expression is studied by in situ hybridization using Oligonucleotide probe, calculated by image processing and macroscopic and microscopic statistics.
  
  
  RESULTS
  Osteocalcin mRNA is expressed in condylar cartilage of young growing SD rats and the acrophase is around 6:00 am. After wearing the functional appliance, the intensity in all-day group rises more than that in 12-hourgroup.
  
  
  CONCLUSIONS
  Better results can be achieved in all-day group with functional appliance.
authors.affiliation: Department of Orthodontics, College of Stomatology, West China University of Medical Sciences, Chengdu 610041, China.
authors.forename: L
authors.initials: L
authors.lastname: Ye
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.forename: S
authors.initials: S
authors.lastname: Luo
mesh_terms: D000818:Animals; D002356:Cartilage / Q000378:metabolism*; D002940:Circadian Rhythm; D008297:Male; D008335:Mandibular Condyle / Q000378:metabolism*; D009971:Orthodontics, Corrective; D015675:Osteocalcin / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D012333:RNA, Messenger; D015675:Osteocalcin