LOW-AMPLITUDE, LOW-FREQUENCY ELECTRIC FIELD-STIMULATED BONE CELL-PROLIFERATION MAY IN PART BE MEDIATED BY INCREASED IGF-II RELEASE

We have developed an in vitro model incorporating a low-amplitude (10(-7) V/cm), low frequency (f < 100 Hz), capacitively coupled electric field in order to study the mechanism through which an electric field may increase bone cell proliferation. Utilizing this model we have previously shown that electric field-stimulated bone cell proliferation was dependent on release of mitogen activity into the culture medium from exposed cells. The current studies were intended to characterize this mitogen activity. In these studies we found that electric field-stimulated human bone cell proliferation was associated with increased IGF-II mRNA accumulation and IGF-II secretion suggesting that IGF-II may in part mediate the increase in bone cell proliferation following electric field exposure.