title: Serotonin regulation in a rat model of exercise-induced chronic fatigue.
abstract: This study investigated the mechanisms underlying regulation of the serotonin system in the rat brain during exercise-induced chronic fatigue. High-performance liquid chromatography-mass spectrometry (HPLC-MS) was performed to measure serum tryptophan of the fatigued rat. HPLC was conducted to measure 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in the frontal cortex and hippocampus. In addition, 5-HT1Areceptor and 5-HT transporter (5-HTT) mRNA expressions were measured at the same locations using real-time PCR. The results demonstrated a significant reduction in the serum tryptophan level in rats with exercise-induced chronic fatigue. Moreover, increased 5-HT and decreased 5-HIAA levels were detected in the frontal cortex and hippocampus, and these alterations were significant. Further, 5-HTT expression was significantly increased and 5-HT1Areceptor expression was significantly decreased. These results indicate that the 5-HT system plays an important role in the development of exercise-induced chronic fatigue. The 5-HT levels in different parts of the brain increased simultaneously, especially at synapses, and these alterations were associated with changes in 5-HTT and 5-HT1AmRNA expressions.
authors.affiliation: Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China. Electronic address: zhandongliu@hotmail.com.
authors.forename: Zhandong
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Centers for Disease Control and Prevention, Atlanta 30329, USA.
authors.forename: Yanjue
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Tianhui
authors.initials: T
authors.lastname: Liu
authors.affiliation: Department of Pharmacy, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Ren
authors.initials: R
authors.lastname: Li
authors.affiliation: China Institute of Sports Medicine, 2-A Sidegate, Tiyuguan Road, Dongcheng District, Beijing 100061, China.
authors.forename: Minhao
authors.initials: M
authors.lastname: Xie
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism / Q000503:physiopathology; D002908:Chronic Disease; D005221:Fatigue / Q000503:physiopathology*; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D010805:Physical Conditioning, Animal; D017208:Rats, Wistar; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*
chemical_list: D050486:Serotonin Plasma Membrane Transport Proteins; D044282:Receptor, Serotonin, 5-HT1A; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid
keywords: 5-HT(1A); 5-HTT; 5-hydroxyindoleacetic acid; 5-hydroxytryptamine; exercise-induced chronic fatigue; tryptophan