Proteome analysis indicates participation of the dorsal hippocampal formation in fear-motivated memory in a time-dependent manner.

Our previous behavioral and molecular data indicate a central role of the dorsal hippocampal formation (dHF) in recent conditioned lick suppression memory. The purpose of this study was to investigate the role of the dHF in recent and remote memory of conditioned lick suppression employing proteomic analysis. Two or 40 days after conditioning, the rats were subjected to a retention test and were then euthanized after 24 hr for dHF collection. We identified 1,165 proteins and quantified 265 proteins. Upregulation of five proteins and downregulation of 21 proteins were found on postconditioning Day 2. Additionally, four proteins were upregulated and 21 proteins were downregulated on postconditioning Day 40. Integrated pathway analysis of the proteomics data indicated changes in the myelin sheath, neuron generation and differentiation, regulation of neurogenesis and synaptic vesicle transport, axonal development, and the growth cone. Our findings provide further support for the role of the dHF in conditioned lick suppression memory and novel insights into the molecular changes that are correlated with recent and remote memory in the dHF, which may be a target for cognitive enhancers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).