Bidirectional effects of hypergravity on the cell growth and differentiated functions of osteoblast-like ROS17/2.8 cells.
A low level of hypergravity (1.5-2.0 G) stimulated the proliferation of ROS17/2.8 cells, whereas it inhibited the differentiated functions of alkaline phosphatase activity and osteocalcin synthesis. These results were just the opposite of our results obtained when the cells were exposed to a high level of hypergravity (40-80 G): inhibition of cell growth and the stimulation of the differentiated functions. The direction of change in the cAMP contents of the cells was also reversed, with a low level of hypergravity causing a decrease in the cAMP content and a high level of hypergravity an increase in it. Therefore, bidirectional effects of hypergravity on the growth and differentiated functions exist in ROS17/2.8 cells according to the magnitude of the hypergravity.
Furutsu
M
M
Biochemistry Laboratory, College of Pharmacy, Nihon University, Chiba, Japan.
Kawashima
K
K
Negishi
Y
Y
Endo
H
H
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001859:Bone Neoplasms / Q000473:pathology; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D018471:Hypergravity / Q000009:adverse effects*; D010006:Osteoblasts / Q000502:physiology*; D015675:Osteocalcin / Q000378:metabolism; D012516:Osteosarcoma / Q000473:pathology; D051381:Rats; D014407:Tumor Cells, Cultured
D015675:Osteocalcin; D000242:Cyclic AMP; D000469:Alkaline Phosphatase