[Effect of continuously compressive pressure on the expression of RANKL mRNA in human periodontal ligament cells in vitro].
OBJECTIVE
To determine the effect of continuously compressive pressure (CCP) on the expression of receptor activator of nuclear factor kappa B ligand (RANKL) in human periodontal ligament cells (HPDLCs) and to investigate the role of RANKL in alveolar bone rebuilding during orthodontic tooth movement.


METHODS
The primary HPDLCs were isolated from human periodontal ligament by explanting enzymatic digestion with trypsin and collagenase to establish a pressure model. Top-bottom axial pressures (1, 2, and 3 g/cm(2)) were laid on HPDLCs for 0.5, 1.5, 6, 12, 24, and 48 h, respectively. The RANKL expression was identified by the reverse transcription-polymerase chain reaction (RT-PCR) at the mRNA level.


RESULTS
The expression of RANKL mRNA significantly increased in a time-dependent manner (P<0.01), so did the value of pressure, especially in the 2 g/cm(2) group (P<0.05).


CONCLUSIONS
CCP can up-regulate the expression of RANKL mRNA in human periodontal ligament cells.
Huang
Sheng-gao
SG
Department of Stomatology, Second Xiangya Hospital, Central South University, Changsha 410011, China. huang_shg@126.com
Zhang
Jian-xing
JX
Xiong
Pei-ying
PY
Wang
Ming-lang
ML
D019245:Compressive Strength; D006801:Humans; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism*; D053245:RANK Ligand / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000235:genetics / Q000378:metabolism*; D013314:Stress, Mechanical
D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B