Examination of Diurnal Variation and Sex Differences in Hippocampal Neurophysiology and Spatial Memory.

Autor:	Goode LK; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham Heersink School of Medicine, Birmingham 35233, AL., Fusilier AR; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham Heersink School of Medicine, Birmingham 35233, AL., Remiszewski N; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham Heersink School of Medicine, Birmingham 35233, AL., Reeves JM; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham Heersink School of Medicine, Birmingham 35233, AL., Abiraman K; Prescott Medical Communications Group, Chicago 60601, IL., Defenderfer M; Research Computing, Information Technology, University of Alabama at Birmingham, Birmingham 35233, AL., Paul JR; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham Heersink School of Medicine, Birmingham 35233, AL., McMahon LL; Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham 35233, AL., Gamble KL; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham Heersink School of Medicine, Birmingham 35233, AL klgamble@uab.edu.
Jazyk:	angličtina
Zdroj:	ENeuro [eNeuro] 2022 Nov 15; Vol. 9 (6). Date of Electronic Publication: 2022 Nov 15 (Print Publication: 2022).
DOI:	10.1523/ENEURO.0124-22.2022
Abstrakt:	Circadian rhythms are biological processes that cycle across 24 h and regulate many facets of neurophysiology, including learning and memory. Circadian variation in spatial memory task performance is well documented; however, the effect of sex across circadian time (CT) remains unclear. Additionally, little is known regarding the impact of time-of-day on hippocampal neuronal physiology. Here, we investigated the influence of both sex and time-of-day on hippocampal neurophysiology and memory in mice. Performance on the object location memory (OLM) task depended on both circadian time and sex, with memory enhanced at night in males but during the day in females. Long-term synaptic potentiation (LTP) magnitude at CA3-CA1 synapses was greater at night compared with day in both sexes. Next, we measured spontaneous synaptic excitation and inhibition onto CA1 pyramidal neurons. Frequency and amplitude of inhibition was greater during the day compared with night, regardless of sex. Frequency and amplitude of excitation was larger in females, compared with males, independent of time-of-day, although both time-of-day and sex influenced presynaptic release probability. At night, CA1 pyramidal neurons showed enhanced excitability (action potential firing and/or baseline potential) that was dependent on synaptic excitation and inhibition, regardless of sex. This study emphasizes the importance of sex and time-of-day in hippocampal physiology, especially given that many neurologic disorders impacting the hippocampus are linked to circadian disruption and present differently in men and women. Knowledge about how sex and circadian rhythms affect hippocampal physiology can improve the translational relevancy of therapeutics and inform the appropriate timing of existing treatments. (Copyright © 2022 Goode et al.)
Databáze:	MEDLINE
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