Skip to main page content
U.S. flag
See More

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007;17(11):1017-22.
doi: 10.1002/hipo.20348.

Running induces widespread structural alterations in the hippocampus and entorhinal cortex

Alexis M Stranahan  1 , David Khalil, Elizabeth Gould
Affiliations

Running induces widespread structural alterations in the hippocampus and entorhinal cortex

Alexis M Stranahan et al. Hippocampus. 2007.

Abstract

Physical activity enhances hippocampal function but its effects on neuronal structure remain relatively unexplored outside of the dentate gyrus. Using Golgi impregnation and the lipophilic tracer DiI, we show that long-term voluntary running increases the density of dendritic spines in the entorhinal cortex and hippocampus of adult rats. Exercise was associated with increased dendritic spine density not only in granule neurons of the dentate gyrus, but also in CA1 pyramidal neurons, and in layer III pyramidal neurons of the entorhinal cortex. In the CA1 region, changes in dendritic spine density are accompanied by changes in dendritic arborization and alterations in the morphology of individual spines. These findings suggest that physical activity exerts pervasive effects on neuronal morphology in the hippocampus and one of its afferent populations. These structural changes may contribute to running-induced changes in cognitive function.

PubMed Disclaimer

Figures

FIGURE 1
FIGURE 1
Physical activity increases dendritic spine density and alters dendritic complexity in multiple cell types. (A) Running increased the density of dendritic spines on the basal dendrites of Golgi-impregnated pyramidal cells in the entorhinal cortex (EC); increased spine density was also observed in the basal and apical dendritic trees of neurons in the hippocampal CA1 region. As previously reported (Eadie et al., 2005; Redila et al., 2006), running increased the density of dendritic spines on dentate gyrus granule neurons (DG). (B) We also used the lipophilic tracer DiI to visualize spines within the same group of animals, and observed similar results. DiI-labeled neurons in the brains of runners show increased spine density in the same regions where changes were observed with Golgi impregnation. (C) Running was associated with increased dendritic length in the DG. (D) Physical activity increased the number of branch points in the apical dendritic tree of CA1 pyramidal neurons, and in DG granule neurons. (*) indicates significance (P < 0.05) following 2-tailed unpaired student's t-test. EC, entorhinal cortex; CA1, hippocampal CA1 field; DG, dentate gyrus.
FIGURE 2
FIGURE 2
Golgi impregnated and DiI labeled neurons. (A) Golgi-impregnated pyramidal neuron in layer III of entorhinal cortex. (B) Golgi-impregnated pyramidal neuron in the CA1 sub-field of the hippocampus. (C) Golgi-impregnated granule neurons in the dentate gyrus of the hippocampus. (D) DiI-labeled pyramidal neuron in layer III of entorhinal cortex. (E) DiI-labeled pyramidal neuron in the CA1 subfield of the hippocampus. (F) DiIlabeled granule neurons in the dentate gyrus. For each cell type, the upper right panel shows a dendritic segment from a control animal, and the lower right micrograph shows a segment from a runner. Segments shown are from secondary dendrites for all cell types. For pyramidal neurons of the entorhinal cortex and CA1 region, the segments are from the basal dendritic tree. Arrows indicate dendritic spines. Scale bars shown with dendritic segments are 5 μm; scale bars shown with cells are 25 μm.
FIGURE 3
FIGURE 3
Running alters the morphology of individual dendritic spines in area CA1 of the rat hippocampus. (A) Dendritic segments from the apical and basal trees of CA1 pyramidal neurons in the hippocampus of control animals and runners. Scale bar = 2 μm. (B) Rats that ran for 60 days have longer dendritic spines on CA1 pyramidal cells relative to sedentary controls. No changes in spine length were observed on pyramidal neurons in the entorhinal cortex (EC) or on granule neurons of the dentate gyrus (DG). (C) Running is associated with reduced spine head area in CA1 pyramidal cells, suggestive of an increase in filopodia. No changes in spine head area were observed in other regions. (*) indicates significance (P < 0.05) following 2-tailed unpaired student's t-test.
See this image and copyright information in PMC

References

    1. Anderson BJ, Rapp DN, Baek DH, McCloskey DP, Coburn-Litvak PS, Robinson JK. Exercise influences spatial learning in the radial arm maze. Physiol Behav. 2000;70:425–429. - PubMed
    1. Baruch DE, Swain RA, Helmstetter FJ. Effects of exercise on Pavlovian fear conditioning. Behav Neurosci. 2004;118:1123–1127. - PubMed
    1. Baylor AM, Spirduso WW. Systematic aerobic exercise and components of reaction time in older women. J Gerontol. 1988;43:121–126. - PubMed
    1. Briones TL, Suh E, Jozsa L, Rogozinska M, Woods J, Wadowska M. Changes in number of synapses and mitochondria in presynaptic terminals in the dentate gyrus following cerebral ischemia and rehabilitation training. Brain Res. 2005;1033:51–57. - PubMed
    1. Buitrago MM, Schulz JB, Dichgans J, Luft AR. Short and longterm motor skill learning in an accelerated rotarod training paradigm. Neurobiol Learning Mem. 2004;81:211–216. - PubMed

Publication types

MeSH terms