Kainate resistant neurons in peripheral ganglia of the rat.

Neurons of dorsal root ganglia and of superior cervical ganglia did not display any morphological signs of degeneration when kainic acid (KA) was administered either systemically (20 and 40 mg/kg) or when it was directly injected (1 microgram). The KA doses used were sufficient to result in heavy destruction of hippocampal CA3/CA4 neurons and neurodegeneration of various brain regions after intracerebroventricular or local application, respectively. The resistance of the peripheral neurons to KA is discussed as a consequence of lacking glutamate inputs.