Electrophysiological properties of lemniscal afferents in rat after kainic acid lesions in the ventrobasal thalamus.

Kainic acid (KA) has been largely used as a neurotoxin, and its axon-sparing effect being repeatedly emphasized, on the basis of anatomical and biochemical data. The present study examines this 'axon-sparing' effect from an electrophysiological point of view and demonstrates that lemniscal fibers retain the capacity to convey somesthetic information 5-60 days after an injection of KA in the ventrobasal complex of the thalamus depriving these afferent fibers of their target cells.