[Effect of calcitonin gene-related peptide on RUNX2 expression in primary rat osteoblasts].
OBJECTIVE
To investigate the effects of exogenous calcitonin gene-related peptide (CGRP) on RUNX2 expression in primary cultured rat osteoblasts.


METHODS
Primary cultured rat osteoblasts were obtained by collagenase / trypsinenzyme digestion from calvarial bone of neonate rats and were  identified by ALP staining; The cells were exposed to gradient concentrations,  and the effect of CGRP on the proliferation of osteoblasts was determined  by MTT assay. The expressions of RUNX2 were quantified by RT-PCR and Western blotting after 48-hour exposure to different CGRP concentrations.


RESULTS
CGRP could promote the proliferation of osteoblasts .When the concentration of CGRP were at 10(-8)-10(-6) mol/L, the proliferation rates of  osteoblasts were 71.9%, 142.1%, 321.0%, respectively (P<0.05); when CGRP was at concentrations of 10(-7) and 10(-6) mol /L in osteoblasts for 48 h, the  mRNA levels of RUNX2 was significantly increased, which increased (46.2±11.2)% and (58.6±14.0)% respectively (P<0.05); the expression of RUNX2  protein levels was consistent with the change of the mRNA levels.


CONCLUSIONS
CGRP could promote RUNX2 expression in primary cultured rat  osteoblasts, which suggests that RUNX2 is involved in the mechanism of osteoblast proliferation induced by CGRP.
Institute of Clinical Molecular Biology, Peking University People's Hospital, Beijing 100044, China.
Na
N
Han
Bao-guo
BG
Jiang
Tian-bing
TB
Wang
Pei-xun
PX
Zhang
Yu-hui
YH
Kou
Dian-ying
DY
Zhang
D000818:Animals; D000831:Animals, Newborn; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism*; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D012886:Skull / Q000166:cytology
D050659:Core Binding Factor Alpha 1 Subunit; D012333:RNA, Messenger; C493717:Runx2 protein, rat; D015740:Calcitonin Gene-Related Peptide