Acute stress exposure preceding transient global brain ischemia exacerbates the decrease in cortical remodeling...

Area of Science:

• Neuroscience
• Cell Biology
• Neuroplasticity

Background:

• Doublecortin (DCX)-immunoreactive cells are crucial for adult brain remodeling.
• Previous studies showed stress or global brain ischemia (GBI) reduces DCX-ir cells in the cingulate cortex (Cg).

Purpose of the Study:

• To investigate if acute stress preconditioning worsens the decrease of DCX-ir cells post-GBI.
• To examine the effect on the anterior cingulate cortex (ACC) and retrosplenial cortex (RS).

Main Methods:

• Rats were divided into three groups: stress preconditioning before GBI (Group P), GBI only (Group G), and controls (Group C).
• Acute stress was induced via forced swim; GBI was induced by carotid artery occlusion.
• DCX-ir cells were quantified in the ACC and RS.

Main Results:

• GBI significantly decreased DCX-ir cells in both ACC and RS, regardless of stress preconditioning.
• Stress preconditioning (Group P) led to a significant further decrease in DCX-ir cells in the RS compared to GBI alone (Group G).
• DCX-ir cells frequently co-localized with parvalbumin, a GABAergic marker.

Conclusions:

• Global brain ischemia reduces the potential for cortical remodeling by decreasing GABAergic neurons in the cingulate cortex.
• Acute stress preconditioning exacerbates this reduction in the retrosplenial cortex post-GBI.