Treadmill exercise enhances passive avoidance learning in rats: the role of down-regulated serotonin system in the limbic system

Abstract

Event Abstract Back to Event Treadmill exercise enhances passive avoidance learning in rats: the role of down-regulated serotonin system in the limbic system Chauying J. Jen1*, L. C. Lin1, F. S. Wu1, Y. C. Ho1 and H. I. Chen1 1 Department of Physiology, College of Medicine, National Cheng Kung University, Taiwan While serotonin (5-HT) may impair learning and memory, exercise has been reported to improve them. It is uncertain whether chronic exercise can facilitate fear memory and long-term potentiation (LTP) via regulating the serotonin system. The effects of 4-wk treadmill exercise training on passive avoidance learning performance and on high-frequency stimulation-induced LTP in brain slices were examined using male Sprague-Dawley rats. Additionally, we quantified levels of 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA), the protein expression of its receptor 5-HT1A and transporter in the amygdala, hippocampus and prefrontal cortex. Our results demonstrated that treadmill exercise improved the passive avoidance learning performance and enhanced the LTP in hippocampal dentate gyrus and lateral amygdala. Administration of 8-hydroxy-di-n-propylamino tetralin (8-OH-DPAT), a selective 5-HT1A receptor agonist, impaired the passive avoidance performance and completely abolished the exercise-improved fear memory. Similarly, the exercise-enhanced LTP in brain slices was eliminated by bath application of 8-OH-DPAT. Our results showed that exercise decreased the 5-HT level in the hippocampus and the expression of 5-HT1A receptor in the amygdala without altering the transporter expression. These data suggest that down-regulation of the 5-HT system in the limbic system, i.e., the reduction of the hippocampus 5-HT content and the amygdala 5-HT1A receptor expression, may be involved in the exercise-enhanced fear memory. Conference: 10th International Conference on Cognitive Neuroscience, Bodrum, Turkey, 1 Sep - 5 Sep, 2008. Presentation Type: Poster Presentation Topic: Memory & Learning Citation: Jen CJ, Lin LC, Wu FS, Ho YC and Chen HI (2008). Treadmill exercise enhances passive avoidance learning in rats: the role of down-regulated serotonin system in the limbic system. Conference Abstract: 10th International Conference on Cognitive Neuroscience. doi: 10.3389/conf.neuro.09.2009.01.285 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 09 Dec 2008; Published Online: 09 Dec 2008. * Correspondence: Chauying J Jen, Department of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, jen@mail.ncku.edu.tw Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Chauying J Jen L. C Lin F. S Wu Y. C Ho H. I Chen Google Chauying J Jen L. C Lin F. S Wu Y. C Ho H. I Chen Google Scholar Chauying J Jen L. C Lin F. S Wu Y. C Ho H. I Chen PubMed Chauying J Jen L. C Lin F. S Wu Y. C Ho H. I Chen Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.