title: [Effects of mechanical stretching force on osteoblast-like function of human periodontal ligament cells in vitro].
abstract: OBJECTIVE
  To investigate the osteoblast-like functional characteristics exhibited by human periodontal ligament cells (hPDLCs) under mechanical force.
  
  
  METHODS
  Human PDLCs cultured in vitro were stretched by mechanical force. Radioimmunoassay (RIA) was used to measure the expression of secreting alkaline phosphotase (ALP) and osteocalcin (OCN). The non-secreting ALP, OCN and osteopontin (OPN) in cells were determined by immunohistochemistry.
  
  
  RESULTS
  It exhibited increasing of ALP secreted into conditional media, and in the 24 hour period there were two peaks which appeared at the 2nd and 4th hour and the 24th hour (P < 0.01). While in the late of the 24 hours, expression of OCN in conditional media increased (P < 0.05).
  
  
  CONCLUSIONS
  Mechanical force induces hPDLCs to differentiate into functional osteoblast-like cells and plays a role in bone remodeling.
authors.affiliation: Department of Orthodontics, Peking University School of Stomatology, Beijing 100081, China.
authors.forename: Xiaotong
authors.initials: X
authors.lastname: Li
authors.forename: Ding
authors.initials: D
authors.lastname: Zhang
authors.forename: Minkui
authors.initials: M
authors.lastname: Fu
authors.forename: Yanqi
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D002478:Cells, Cultured; D006801:Humans; D015675:Osteocalcin / Q000032:analysis; D010010:Osteoclasts / Q000502:physiology*; D053495:Osteopontin; D010513:Periodontal Ligament / Q000166:cytology*; D012795:Sialoglycoproteins / Q000032:analysis; D013314:Stress, Mechanical
chemical_list: C506895:SPP1 protein, human; D012795:Sialoglycoproteins; D015675:Osteocalcin; D053495:Osteopontin; D000469:Alkaline Phosphatase