Electric Field Suppression Of Epileptiform Activity In Hippocampal Slices. Gluckman, Bruce J., Emily J. Neel, Theoden I. Netoff, William L. Ditto, Mark L. Spano, and Steven J. Schiff. Naval Surface Warfare Center, White Oak Laboratory, Silver Spring, MD 20903 USA, Department of Neurosurgery, Children's National Medical Center and the George Washington University School of Medicine, Washington, DC USA, Program in Neuroscience, The George Washington University, Washington, DC USA.
APStracts 3:0196N, 1996.
1) The effects of relatively small external DC electric fields on synchronous activity in CA1 and CA3 from transverse and longitudinal type hippocampal slices were studied. 2) To record neuronal activity during significant field changes, differential DC amplification was employed with a reference electrode aligned along an isopotential with the recording electrode. 3) Suppression of epileptiform activity was observed in 31 of 33 slices independent of region studied and type of slice, but was highly dependent on field orientation with respect to the apical dendritic-somatic axis. 4) Modulation of neuronal activity in these experiments was readily observed at field strengths at or below 5-10 mV/mm. Suppression was seen with the field oriented (positive to negative potential) from the soma to the apical dentrites. 5) In Vivo application of these results may be feasible.

Received 17 July 1996; accepted in final form 11 September 1996.
APS Manuscript Number J571-6.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 7 October 1996