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Updated: Dec 13, 2025

Transmission Electron Microscopy as the Visualization Technique for Analysis of Circadian Synaptic Plasticity in the Mouse Barrel Cortex
Published on: August 19, 2025
Impact of circadian and diurnal rhythms on cellular metabolic function and neurodegenerative diseases
S Kendall Smith1, Erik S Musiek2
1Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States.
Abstract:
The 24-h rotational period of the earth has driven evolution of biological systems that serve to synchronize organismal physiology and behavior to this predictable environmental event. In mammals, the circadian (circa, "about" and dia, "a day") clock keeps 24-h time at the organismal and cellular level, optimizing biological function for a given time of day. The most obvious circadian output is the sleep-wake cycle, though countless bodily functions, ranging from hormone levels to cognitive function, are influenced by the circadian clock. Here we discuss the regulation of metabolic pathways by the circadian clock, discuss the evidence implicating circadian and sleep disruption in neurodegenerative diseases, and suggest some possible connections between the clock, metabolism, and neurodegenerative disease.
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