Antisense oligodeoxynucleotides to c-fos are amnestic for passive avoidance in the chick.

Induction of c-fos occurs in the forebrain when chicks are trained on a passive avoidance task. Suppression of c-Fos protein synthesis with antisense oligodeoxynucleotides prevented long-term memory retention when injected 10-11 h before training, but not if injections were made between 3 h pre-and 3 h post-training. c-fos expression is thus necessary for long-term memory retention, presumably because of its control of induction of the signalling pathway that ultimately results in the protein synthesis subserving synaptic remodelling.