Transcriptional Regulation of Brain-Derived Neurotrophic Factor in the Amygdala during Consolidation of Fear Memory

We have demonstrated previously that brain-derived neurotro-phic factor (BDNF) signaling in the amygdala is required for the consolidation of fear memory. This study is designed to char-acterize the signal cascades by which fear conditioning mod-ulates transcriptional and translational expression of BDNF. Real-time reverse transcription-coupled polymerase chain re-action showed a significant increase in BDNF exon I- and III-containing mRNA in the amygdala of fear-conditioned rats, indicating that fear conditioning was capable of up-regulating BDNF mRNA. Bilateral administration of actinomycin D or ani-somycin to the amygdala attenuated conditioning-induced in-crease in BDNF protein. Inhibitors for N-methyl-D-aspartate (NMDA) receptor, L-type voltage-dependent calcium channel (L-VDCC), adenylyl cyclase, cAMP-dependent protein kinas