RT Journal Article SR Electronic T1 AFTERHYPERPOLARIZATION AMPLITUDE IN CA1 PYRAMIDAL CELLS OF AGED LONG-EVANS RATS CHARACTERIZED FOR INDIVIDUAL DIFFERENCES JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.05.15.098376 DO 10.1101/2020.05.15.098376 A1 Daniel Severin A1 Michela Gallagher A1 Alfredo Kirkwood YR 2020 UL http://biorxiv.org/content/early/2020/05/16/2020.05.15.098376.abstract AB Altered neural excitability is considered a prominent contributing factor to cognitive decline during aging. A clear example is the excess neural activity observed in several temporal lobe structures of cognitively impaired older individuals in rodents and humans. At a cellular level, aging-related changes in mechanisms regulating intrinsic excitability have been well examined in pyramidal cells of the CA1 hippocampal subfield. Studies in the inbred Fisher 344 rat strain document an age-related increase in the slow afterhyperpolarization (AHP) that normally occurs after a burst of action potentials, and serves to reduce subsequent firing. We evaluated the status of the AHP in the outbred Long-Evans rat, a well-established model for studing individual differences in neurocognitive aging. In contrast to the findings reported in the Fisher 344 rats, in the Long-Evan rats we detected a selective reduction in AHP in cognitively impaired aged individuals. We discuss plausible scenarios to account for these differences and also discuss possible implications of these differences.Competing Interest StatementThe authors have declared no competing interest.