JoVE Encyclopedia of Experiments
Neuroscience
0 views • 1:23 min • March 4th, 2025
Take a chemically-fixed brain from a mouse subjected to chronic stress.
Stress impairs oligodendrocyte function, disrupting the lipid-rich myelin sheath surrounding neuronal axons in the medial prefrontal cortex, a brain region regulating emotion.
Reapply fixative to preserve tissue architecture. Immerse the tissue in a cryoprotectant to replace water, preventing ice crystal formation during freezing.
Freeze the brain, then section it into coronal slices.
Mount the slices onto slides, then rehydrate them in water to enhance stain penetration.
Heat the slices in a solution containing gold ions. These ions selectively bind to lipids in the myelin sheath and form metallic gold deposits, labeling the myelinated neurons.
Heat with a reducing agent to reduce excess gold ions, then rinse to remove them and dehydrate the tissue using increasing alcohol concentrations.
Use xylene to increase tissue transparency and mount the slides.
Using microscopy, visualize the gold-stained myelinated neurons and assess stress-induced changes.