Regulation of reward-related neural pathways and behavior by ghrelin

2016 Fiscal Year Final Research Report

• Project/Area Number: 26460328
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental physiology(including physical medicine and nutritional physiology)
• Research Institution: Kurume University
• Principal Investigator: Kawahara Yukie 久留米大学, 医学部, 准教授 (10279135)
• Co-Investigator(Renkei-kenkyūsha): Kojima Masayasu 久留米大学, 分子生命研究所, 教授 (20202062) ; MIFUNE Hiroharu 久留米大学, 医学部, 准教授 (70174117) ; OHNISHI Yoshinori 久留米大学, 医学部, 助教 (10626865)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: グレリン / ドーパミン / グレリン欠損マウス / 報酬 / ストレス / 行動量

Outline of Final Research Achievements

The present study investigated the role of endogenious ghrelin in reward related-behavior and -central dopamine neural responses using ghrelin knockout mice.
In ghrelin knockout mice, the dopamine responses to the rewarding stimuli were attenuated. Also, the enhancing effects of the long-term rich envioronment with wheel on the dopamine responses to rearding stimuli and on locomotor activity were drastically attenuated. However, social defeat stress-induced decrease of social interaction and increase of cocaine preference were similar to that in wild type mice.
We conclude that ghrelin mediates the enhancement of the dopamine responses in rich environment, but not in stressful experiences. Ghrelin, thereby, consequently increases motivation and locomotor activityin rich environment.

Free Research Field

神経薬理学