Stress-induced dendritic remodeling in the prefrontal cortex is circuit specific

Area of Science:

• Neuroscience
• Stress Research
• Brain Circuitry

Background:

• Chronic stress alters neural structure in various brain regions.
• Distinct patterns of neural remodeling across specific circuits remain unclear.
• The medial prefrontal cortex (mPFC) to basolateral amygdala (BLA) pathway is implicated in stress-related disorders.

Purpose of the Study:

• To investigate if chronic stress uniquely affects dendritic remodeling in the mPFC projections to the BLA.
• To compare stress-induced remodeling in BLA-projecting neurons versus entorhinal cortex (EC)-projecting neurons from the infralimbic (IL) mPFC.

Main Methods:

• Male rats underwent 10 days of immobilization stress.
• Retrograde tracer (FastBlue) injected into BLA or EC to label IL neurons.
• Dendritic arborization and spine density of labeled and unlabeled IL neurons visualized using Lucifer Yellow.

Main Results:

• Stress induced dendritic retraction in apical dendrites of randomly selected and EC-projecting IL neurons.
• BLA-projecting IL neurons exhibited no significant dendritic remodeling following chronic stress.
• No stress-related changes in dendritic spine density were observed in any IL neuron population.

Conclusions:

• The IL-BLA neural pathway demonstrates resilience to chronic stress-induced dendritic remodeling.
• Circuit-specific differences in neural plasticity may underlie vulnerability or resilience to stress-related illnesses.
• Findings highlight the importance of considering neural circuit specificity in stress research.