THE GROWTH OF PC12 NEURITES IS BIASED TOWARDS THE ANODE OF AN APPLIEDELECTRICAL-FIELD

We have exposed cultures of PC12 cells to uniform DC electric fields f ollowing the addition of NGF. The success of these experiments relied upon the design of new chambers enabling fields to be applied to mamma lian cell cultures. After 48 h of field application, the distribution of neurite outgrowths was biased towards the anode. More neurites face d the anode than would be expected if growth was uniform. The magnitud e of this bias was strongly correlated with field strength, with a thr eshold value of about 1 mV/mm. At field strengths above 30 mV/mm, the neurites growing towards the cathode were shorter than those growing t owards the anode or perpendicular to the field. This response was not correlated with field strength. This report confirms that mammalian ne urons respond to electrical fields and supports the notion that neurit es are influenced by endogenous electrical fields during development. As far as we are aware, this is the only report that documents a respo nse towards the anode. (C) 1994 John Wiley and Sons, Inc.