SEIZURE-INDUCED ACTIVATION OF ENKEPHALIN-SYNTHESIZING AND SOMATOSTATIN-SYNTHESIZING NEURONS

The extent of the neuronal network that is activated by kainic acid-in duced seizures was anatomically identified and neurochemically charact erized. Seizure-activated neurons were identified through the immunocy tochemical demonstration of Fos protein in neuronal nuclei. These seiz ure-activated neurons were characterized by determining if they contai ned the mRNA for somatostatin or enkephalin, using in situ hybridizati on procedures. The results demonstrate that a majority of enkephalin- and somatostatin-synthesizing neurons expressed the Fos protein follow ing seizures and that they represent a major component of the kainic a cid-induced, seizure-activated neuronal network.