Senile plaques in cortex of aged normal monkeys

Area of Science:

• Neuroscience
• Primatology
• Pathology

Background:

• Senile plaques are a hallmark of aging and neurodegenerative diseases.
• Understanding plaque composition and distribution is crucial for studying brain aging.

Purpose of the Study:

• To investigate the density, type, and regional distribution of cortical senile plaques in aged rhesus monkeys.
• To explore the potential evolution of plaque types.

Main Methods:

• Analysis of cortical tissue from 6 aged rhesus monkeys.
• Quantification and classification of senile plaques based on neurite and amyloid content.

Main Results:

• Plaque density varied across cortical regions, highest in prefrontal and temporal, lowest in occipital cortex.
• Plaques were categorized as neurite, mixed, or amyloid types.
• Increased total plaque density correlated linearly with a higher proportion of amyloid plaques.

Conclusions:

• Cortical senile plaques exhibit distinct regional distributions in aged rhesus monkeys.
• Evidence suggests a developmental progression of plaque types from neurite-predominant to amyloid-predominant forms.