1. Dissociable effects of advanced age on prefrontal cortical and medial temporal lobe ensemble activity.
- Author
-
Hernandez AR, Reasor JE, Truckenbrod LM, Campos KT, Federico QP, Fertal KE, Lubke KN, Johnson SA, Clark BJ, Maurer AP, and Burke SN
- Subjects
- Animals, Behavior, Animal, CA1 Region, Hippocampal physiology, Cytoskeletal Proteins metabolism, Male, Nerve Tissue Proteins metabolism, Neural Pathways physiology, Rats, Inbred F344, Aging physiology, Association Learning physiology, Neurons physiology, Perirhinal Cortex physiology, Prefrontal Cortex physiology, Temporal Lobe physiology
- Abstract
The link between age-related cellular changes within brain regions and larger scale neuronal ensemble dynamics critical for cognition has not been fully elucidated. The present study measured neuron activity within medial prefrontal cortex (PFC), perirhinal cortex (PER), and hippocampal subregion CA1 of young and aged rats by labeling expression of the immediate-early gene Arc. The proportion of cells expressing Arc was quantified at baseline and after a behavior that requires these regions. In addition, PER and CA1 projection neurons to PFC were identified with retrograde labeling. Within CA1, no age-related differences in neuronal activity were observed in the entire neuron population or within CA1 pyramidal cells that project to PFC. Although behavior was comparable across age groups, behaviorally driven Arc expression was higher in the deep layers of both PER and PFC and lower in the superficial layers of these regions. Moreover, age-related changes in activity levels were most evident within PER cells that project to PFC. These data suggest that the PER-PFC circuit is particularly vulnerable in advanced age., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF