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Updated: May 21, 2026
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Preparation of Acute Hippocampal Slices from Rats and Transgenic Mice for the Study of Synaptic Alterations during Aging and Amyloid Pathology
Published on: March 23, 2011
Morphological and molecular changes in aging rat prelimbic prefrontal cortical synapses
Erik B Bloss1, Rishi Puri, Frank Yuk
1Fishberg Department of Neuroscience and Friedman Brain Institute, Mount Sinai School of Medicine, New York, NY 10029, USA.
Neurobiology of Aging
|June 26, 2012
Summary
Aging reduces small synapse density in the rat prefrontal cortex (PFC). Increased phosphorylated LIM kinase (pLIMK) in large synapses may impair plasticity, contributing to cognitive decline.
Area of Science:
- Neuroscience
- Cell Biology
- Aging Research
Background:
- Age-related cognitive decline is linked to reduced prefrontal cortex (PFC) synaptic plasticity.
- Synaptic plasticity relies on the actin cytoskeleton, regulated by phosphorylated LIM kinase (pLIMK).
Purpose of the Study:
- To investigate how aging affects synaptic density, morphology, and pLIMK expression in the rat prelimbic PFC.
- To explore the role of pLIMK in age-related changes in PFC synapses.
Main Methods:
- Unbiased electron microscopy to quantify synapse density and morphology.
- Postembedding immunogold labeling to assess pLIMK localization and expression.
Main Results:
- Aging decreased small synapse density by approximately 50% while large synapse density remained stable.
- pLIMK expression increased by approximately 50% in aging synapses, localized to the postsynaptic density.
- The increase in pLIMK was specific to the largest subset of prelimbic PFC synapses.
Conclusions:
- Age-related increases in pLIMK may stabilize large synapses by inhibiting actin filament plasticity.
- This mechanism could contribute to age-related impairments in executive functions associated with PFC function.
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