Exercise protects myelinated fibers of white matter in a rat model of depression

The antidepressive effects of exercise have been a focus of research and are hypothesized to remodel the brain networks constructed by myelinated fibers. However, whether the antidepressant effects of exercise are dependent on changes in white matter myelination are unknown. Therefore, we chose chronic unpredictable stress (CUS) as a model of depression and designed an experiment. After a 4‐week CUS period, 40 animals were tested using the sucrose preference test (SPT) and the open field test (OFT). The depressed rats then underwent 4‐week running exercise. Next, electron microscopy and unbiased stereological methods were used to investigate white matter changes in the rats. After the 4‐week CUS stimulation, body weight, sucrose preference and scores on the OFT were significantly lower in the depression rats than in the unstressed rats (p