Embryonic bone matrix formation is increased after exposure to a low-amplitude capacitively coupled electric field, in vitro.
In order to investigate the mechanism(s) of electric field-stimulated osteogenesis, we have developed an in vitro model in which embryonic chick tibiae have consistently demonstrated increased bone matrix formation in response to a low amplitude (estimated 10(-5) V/m in the serum-free culture medium), capacitively coupled, 10 Hz sinusoidal electric field. Initial applications of this model revealed that 72 h of continuous exposure to the electric field increased tibial collagen production by 29% compared to untreated controls, P less than 0.01. Additional studies further revealed: (a) that when electric field exposure was limited to 30 min/day during the 72 h in vitro incubation, embryonic bone matrix formation was increased by 83%, compared to non-treated controls (P less than 0.001), suggesting an inductive mechanism; (b) that the osteogenic response to electric field exposure in vitro was not unique to embryonic chick tibiae, since a similar response was also seen with newborn mouse calvaria (+133%, P less than 0.02); (c) that electric field-exposure-stimulated chick bone matrix formation was associated with increased bone cell proliferation; and (d) that this mitogenic response to in vitro electric field exposure could also be observed with embryonic chick calvarial cells in monolayer, serum-free cultures.
Fitzsimmons
R J
RJ
Farley
J
J
Adey
W R
WR
Baylink
D J
DJ
D000818:Animals; D001857:Bone Matrix / Q000196:embryology*; D002455:Cell Division / Q000528:radiation effects; D003094:Collagen / Q000096:biosynthesis; D004574:Electromagnetic Fields; D004627:Embryonic Induction; D051379:Mice; D009924:Organ Culture Techniques; D010012:Osteogenesis / Q000528:radiation effects*
D003094:Collagen