Intracerebroventricular injection of ghrelin decreases wheel running activity in rats.
There is an increasing interest in elucidating the molecular mechanisms by which voluntary exercise is regulated. In this study, we examined how the central nervous system regulates exercise. We used SPORTS rats, which were established in our laboratory as a highly voluntary murine exercise model. SPORTS rats showed lower levels of serum ghrelin compared with those of the parental line of Wistar rats. Intracerebroventricular and intraperitoneal injection of ghrelin decreased wheel-running activity in SPORTS rats. In addition, daily injection of the ghrelin inhibitor JMV3002 into the lateral ventricles of Wistar rats increased wheel-running activity. Co-administration of obestatin inhibited ghrelin-induced increases in food intake but did not inhibit ghrelin-induced suppression of voluntary exercise in rats. Growth hormone secretagogue receptor (GHSR) in the hypothalamus and hippocampus of SPORTS rats was not difference that in control rats. We created an arcuate nucleus destruction model by administering monosodium glutamate (MSG) to neonatal SPORTS rats. Injection of ghrelin into MSG-treated rats decreased voluntary exercise but did not increase food intake, suggesting that wheel-running activity is not controlled by the arcuate nucleus neurons that regulate feeding. These results provide new insights into the mechanism by which ghrelin regulates voluntary activity independent of arcuate nucleus neurons.
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Yumiko
Y
Miyatake
Department of Integrative Physiology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan; PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan.
Tetsuya
T
Shiuchi
Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Kazuaki
K
Mawatari
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Satomi
S
Toda
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Yasuko
Y
Taniguchi
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Akari
A
Futami
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Fukiko
F
Sato
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Masashi
M
Kuroda
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Mayu
M
Sebe
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Rie
R
Tsutsumi
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Nagakatsu
N
Harada
Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan.
Yasuhiko
Y
Minokoshi
Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Maebashi, Gunma University, 371-8512, Japan.
Tadahiro
T
Kitamura
Department of Endocrinology, Metabolism, Rheumatology and Nephrology, Faculty of Medicine, Oita University, Yufu, Oita, 879-5593, Japan.
Koro
K
Gotoh
Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Miki, Kagawa, 761-0793, Japan.
Masaki
M
Ueno
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan.
Yutaka
Y
Nakaya
Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Tokushima, 770-8503, Japan. Electronic address: hsakaue@tokushima-u.ac.jp.
Hiroshi
H
Sakaue
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects / Q000378:metabolism; D004435:Eating / Q000187:drug effects; D054439:Ghrelin / Q000008:administration & dosage / Q000378:metabolism*; D057967:Infusions, Intraventricular; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D010805:Physical Conditioning, Animal; D051381:Rats; D017208:Rats, Wistar; D012420:Running / Q000502:physiology*; D012970:Sodium Glutamate / Q000008:administration & dosage
D054439:Ghrelin; D012970:Sodium Glutamate
Central nervous system; Ghrelin; Voluntary exercise