Enhancement of NGF gene expression in rat brain by the memory-enhancing peptide AVP(4-8).

Northern blot analysis of nerve growth factor (NGF) was used to evaluate the effect of exogenous AVP(4-8) on the transcription of NGF gene in rat brain. NGF expression was found to be significantly enhanced by exogenous AVP(4-8) in the hippocampus as well as in the cerebral cortex in a time period of 12 h. This effect was inhibited by an antagonist to AVP(4-8). In addition, gel mobility shift assay was also used to observe the in vitro expression of c-fos gene in rat hippocampal slices. Our results suggest that NGF gene is one of the target genes responsible for memory-enhancing responses induced by AVP(4-8) and that the enhancement of NGF gene expression may share the signaling pathway mediated by AVP(4-8) receptor and c-fos gene expression.