The effect of treadnill running training on neural plasticity in the hippocampus in juverile rats.

2001 Fiscal Year Final Research Report Summary

• Project/Area Number: 11480004
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 体育学
• Research Institution: Institute of Health and Sports Sciences, University of Tsukuba
• Principal Investigator: SOYA Hideaki Institute of Health and Sports, Sciences, Associate Professor, 体育科学系, 助教授 (50221346)
• Co-Investigator(Kenkyū-buntansha): FUJIKAWA Takahiko Mie University School of Medicine, Department of Biochemistry, Lecturer, 医学部・生化学, 講師 (60293776) ; TAKITA Masatoshi University of Tsukuba, Neurobionics Natl Inst of Advanced Indastrial sciated, 人間福祉医工学, 主任研究員
• Project Period (FY): 1999 – 2001
• Keywords: running / BDNF / plasticity / neurogenesis / morris-wader maze

Research Abstract

In this study, we investigated following three experiments. First, we examined whether acute running at the lactate threshold (LT) acts on the dentate gyms (DG) to induce BDNF mRNA expression, we used a running model using Wistar male rats (Experiment 1). Second, we examined whether chronic running training either or above the LT specifically causes up-regulation of BDNF mRNA in the DG (Experiment 2). Finally, we estimated how the same types of exercise affects neurogeniesis in DG. In the experiment 1, exercise induced BDNF mRNA expressions, but these expressions were not observed depending on exercise intensity. These results suggest that the hippocampus would be activated even by low exercise intensity in acute single bout of exercise.
In the experiment 2, rats were subjected to Naive (N: sedentary), and to 4 weeks of running training either below-(4W: walking) or supra-(4T, trotting) LT The effects of these training on hippocampal BDNF mRNA and morris water maze were examined. Unlike the experiment 1, the BDNF mRNA levels in the DG were observed to be up-regulated in rats in 41 but not in 4W Since plasma corticosterone levels and adrenal weight in 4T were significantly higher than those in N, chronic exericse increased hippocampal neuroplastisity though stress response occurred concurrently. There were no significant differences in spatial learning in the morris water maze. Thus we failed to confirm the hippocampal neuroplastisity by behavioral approach.
These results suggest that acute LT running has the potential role of inducing BDNF mRNA expression in the DG. Adaptive up-regulation of BDNF mRNA expression can be induced by light running below the LT in acute running, and also can be induced by high intensity running (supra-LT) in chronic running. In addition, chronic running tended to be induced neurogenesis (Experiment 3), indicating exercise training would be increased hippocampal plastisity.
It is worth examining that exercise induced hippocampal plastisity can be detected by morris water maze again, or some other behavioral approaches.