Ventral striatal plasticity and spatial memory.

Spatial memory formation is a dynamic process requiring a series of
cellular and molecular steps, such as gene expression and protein
translation, leading to morphological changes that have been
envisaged as the structural bases for the engram. Despite the role
suggested for medial temporal lobe plasticity in spatial memory,
recent behavioral observations implicate specific components of
the striatal complex in spatial information processing. However, the
potential occurrence of neural plasticity within this structure after
spatial learning has never been investigated. In this study we
demonstrate that blockade of cAMP response element binding
protein-induced transcription or inhibition of protein synthesis or
extracellular proteolytic activity in the ventral striatumimpairs longterm
spatial memory. These findings demonstrate that, in the ventral
striatum, similarly to what happens in the hippocampus, several
key molecular events crucial for the expression of neural plasticity
are required in the early stages of spatial memory formation.