C-JUN MESSENGER-RNA EXPRESSION IN THE HIPPOCAMPAL-FORMATION INDUCED BY RESTRAINT STRESS

The effect of restraint stress on c-jun mRNA expression in the hippoca mpal formation was investigated by in situ hybridization, dot blot and northern blot. c-jun mRNA expression increased after 60 min of forced restraint in the dentate gyrus, CA1 and CA3 regions of the hippocampa l formation. The effect in the dentate gyrus was attenuated by pre-str ess i.c.v. injection of the anxiolytic benzodiazepine midazolam (20 nm ol/2 mu l) or the N-methyl-D-aspartate (NMDA) receptor antagonist 2-am ino-7-phosphonoheptanoic acid (AP-7, 5 nmol/2 mu l), but not by the 5- HT1A agonist, (+/-) 8-hydroxy-dipropylaminotetralin (X-OH DPAT, 20 nmo l/2 mu l). These results suggest that the hippocampal formation is act ivated during restraint stress, and that this activation is modulated by benzodiazepine/GABA-A or NMDA receptors. (C) 1977 Elsevier Science B.V.