Ensemble-specific deficit in neuronal intrinsic excitability in aged mice.
Neurobiol Aging
; 123: 92-97, 2023 03.
Article
in En
| MEDLINE
| ID: mdl-36652783
ABSTRACT
With the prevalence of age-related cognitive deficits on the rise, it is essential to identify cellular and circuit alterations that contribute to age-related memory impairment. Increased intrinsic neuronal excitability after learning is important for memory consolidation, and changes to this process could underlie memory impairment in old age. Some studies find age-related deficits in hippocampal neuronal excitability that correlate with memory impairment but others do not, possibly due to selective changes only in activated neural ensembles. Thus, we tagged CA1 neurons activated during learning and recorded their intrinsic excitability 5 hours or 7 days post-training. Adult mice exhibited increased neuronal excitability 5 hours after learning, specifically in ensemble (learning-activated) CA1 neurons. As expected, ensemble excitability returned to baseline 7 days post-training. In aged mice, there was no ensemble-specific excitability increase after learning, which was associated with impaired hippocampal memory performance. These results suggest that CA1 may be susceptible to age-related impairments in post-learning ensemble excitability and underscore the need to selectively measure ensemble-specific changes in the brain.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Learning
/
Neurons
Type of study:
Risk_factors_studies
Limits:
Animals
Language:
En
Journal:
Neurobiol Aging
Year:
2023
Document type:
Article
Affiliation country:
United States