[Effects of hypotonic solution on the proliferation, alkaline phosphatase activity and [Ca2+]i concentration of osteoblast-like cells].
OBJECTIVE
To investigate the effects of static-stretch from the hypotonic solution on the proliferation, alkaline phosphatase activity and [Ca2+]i in the osteoblast-like cells.


METHODS
Mechanical loading was introduced by swelling in the hypotonic solution. In vitro cultured MG63 were incubated under continuous swelling of 277, 240 and 163mOsm for 2h, 4h, 8h, 12h, 24h and 48h. The cell proliferation was detected by MTT assay. ALPase and [Ca2+]i were determined by modified enzyme dynamic method and OCPC respectively.


RESULTS
The cell proliferation, ALP activity and [Ca2+]i increased slowly under continuous static-stretch of 277 and 240mOsm. The cell proliferation was inhibited under 163mOsm, with a sharp increase of [Ca2+]i at 8h (11.383 +/- 0.111) and an increase of ALPase activity (0.326 +/- 0.002).


CONCLUSIONS
The static-stretch induced from the hypotonic solution has an impact on the proliferation, differentiation, ALPase and Ca2+-ATPase of the MG63. The [Ca2+]i is correlated with the ALPase.
Zhang
Wei-qun
WQ
Department of Prosthodontics, West China Stomatological Hospital, Sichuan University, Chengdu 610041, China.
Zhu
Zhi-min
ZM
Chao
Yong-lie
YL
Lei
Yu
Y
Cui
Jun
J
D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D007038:Hypotonic Solutions / Q000494:pharmacology*; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*
D007038:Hypotonic Solutions; D000469:Alkaline Phosphatase; D002118:Calcium