LTP mechanisms in the dentate gyrus in vivo

This book illustrates some of the various molecular
mechanisms underlying synaptic plasticity in a
subfield of the rat hippocampus called dentate
gyrus (DG). Long-term potentiation (LTP) is a well-
known model for studying strengthening of synaptic
plasticity. In this study, LTP was induced in the
DG by intrahippocampal infusion of brain-derived
neurotrophic factor (BDNF-LTP). Alternatively, LTP
was induced at medial perforant path-granule cell
synapses by high frequency stimulation (HFS-LTP).
The aim of the study was investigation of
transcriptional and translational changes of
activity-regulated cytoskeleton-associated protein
(Arc/Arg3.1) as well as changes in activation of the
translation factors eIF4E (eukaryotic initiation
factor 4E) and eEF2 (eukaryotic elongation factor-2)
during LTP.
We have demonstrated rapid activation of both
translation factors and upregulation of Arc protein
during BDNF-LTP. Additionally, an approach based on
intrahippocampal infusion of Arc antisense
oligodeoxynucleotides showed the importance of
sustained Arc translation for the maintenance of
both BDNF-LTP and HFS-LTP during a restricted time
window.