[Substance P regulates function of osteoclasts via neurokinin-1 receptor].
OBJECTIVE
To investigate the effects of substance P on cultured rat osteoclasts.


METHODS
Neurokinin-1 (NK1) receptor expression in osteoclasts was examined by immunohitochemical method, and changes of bone resorption activity caused by substance P and NK1 receptor antagonists were detected by pit formation assay.


RESULTS
Immunoreactivity for NK1 receptor was distributed in the cytoplasm of osteoclasts. The average of pit formation areas significantly increased with addition of substance P (10(-7)-10(-4) mol/L) (P < 0.05), but the number of pitformations did not change (P > 0.05). NK1 receptor antagonists inhibited the enhancement of the bone resorption by substance P addition.


CONCLUSIONS
The findings suggested that substance P may stimulate osteoclasts and result in bone resorption by the mediation of NK1 receptor.
Sun
Ying-Ming
YM
Dept. of Orthodontics, West China College of Stomatology, Sichuan University, Chengdu 610041, China.
Luo
Song-Jiao
SJ
Zhao
Yu-Hui
YH
D000818:Animals; D010010:Osteoclasts; D051381:Rats; D018040:Receptors, Neurokinin-1; D013373:Substance P
D018040:Receptors, Neurokinin-1; D013373:Substance P