Expression of mRNAs encoding flip isoforms of GluR1 and GluR2 glutamate receptors is increased in rat hippocampus in epilepsy induced by tetanus toxin

The messenger RNAs encoding the flip and flop isoforms of the glutamate rec eptor subunits GluR1 and GluR2 were detected and quantified by in situ hybr idization in the hippocampal formation of rats following intrahippocampal i njection of tetanus on one side. The mRNAs encoding the flip isoforms of bo th GluR1 and GluR2 were significantly increased 4 weeks after injection. Th e GluR1 flip mRNA was significantly elevated only in the dentate gyrus, whe reas significant increases in the GluR2 flip mRNA were seen in all hippocam pal subfields examined. There were no significant changes in the mRNA encod ing the hop isoforms of either GluR1 or GluR2. The significant changes in f lip isoform mRNAs occurred on both sides. (C) 1999 Published by Elsevier Sc ience B.V. All rights reserved.