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Updated: Aug 9, 2026
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Trace Fear Conditioning in Mice
Published on: March 20, 2014
Fear conditioning drives profilin into amygdala dendritic spines
Raphael Lamprecht1, Claudia R Farb, Sarina M Rodrigues
1W.M. Keck Foundation Laboratory for Neurobiology, Center for Neural Science, New York University, New York, New York 10003, USA. rlamp@research.haifa.ac.il
Nature Neuroscience
|March 21, 2006
Summary
Fear conditioning in rats involves profilin movement into dendritic spines, causing enlargements. This spine morphology change in the lateral amygdala may enhance memory formation and synaptic responses.
Area of Science:
- Neuroscience
- Molecular Biology
- Cell Biology
Background:
- Spine morphology changes are linked to memory formation.
- Molecular mechanisms driving these alterations are not well understood.
Purpose of the Study:
- To investigate the molecular mechanisms of spine morphology changes during fear conditioning.
- To identify proteins involved in structural plasticity in the lateral amygdala.
Main Methods:
- Fear conditioning in rats.
- Immunofluorescence to track protein localization (profilin).
- Microscopy to analyze dendritic spine morphology and postsynaptic densities (PSDs).
Main Results:
- Fear conditioning induced profilin movement into dendritic spines in the lateral amygdala.
- These profilin-containing spines exhibited enlarged postsynaptic densities (PSDs).
- A higher ratio of spines with profilin and enlarged PSDs was observed post-learning.
Conclusions:
- Profilin's role in actin polymerization is crucial for fear learning-induced spine enlargement.
- Enlarged PSDs in profilin-containing spines may enhance synaptic plasticity in the lateral amygdala.
- These molecular and structural changes contribute to fear memory consolidation.
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