Faculty Articles

Voluntary running-wheel exercise decreases the threshold for rewarding intracranial self-stimulation.

Publication Title

Behavioral neuroscience

ISSN

0735-7044

Publication Date

8-1-2012

Keywords

antidepressant effects, electrical self-stimulation, hedonic state, lateral hypothalamus, lhss, mood enhancement, physical exercise, prolonged running, rats, reward sensitivity, running wheel, voluntary exercise, depression model, reward threshold, neurobehavioral mechanisms, exercise neuroscience

Abstract

Physical exercise has mood-enhancing and antidepressant properties although the mechanisms underlying these effects are not known. The present experiment investigated the effects of prolonged access to a running wheel on electrical self-stimulation of the lateral hypothalamus (LHSS), a measure of hedonic state, in rats. Rats with continuous voluntary access to a running wheel for either 2 or 5 weeks exhibited dramatic leftward shifts in the effective current 50 (ECu50; current value that supports half of maximum responding) of their LHSS current-response functions compared to their baselines, indicating a decrease in reward threshold, whereas control rats current-response functions after 2 or 5 weeks were not significantly different from baseline. An inverse correlation existed between the change in ECu50 from baseline and the amount an animal had run in the day prior to LHSS testing, indicating that animals that exhibited higher levels of running showed a more robust decrease in LHSS threshold. We conclude that long-term voluntary exercise increases sensitivity to rewarding stimuli, which may contribute to its antidepressant properties.

DOI

10.1037/a0029149

Volume

126

Issue

4

First Page

582

Last Page

7

Disciplines

Medical Specialties | Medicine and Health Sciences | Osteopathic Medicine and Osteopathy

This document is currently not available here.

Find in your library

Share

COinS