Brain regional serotonin synthesis following adaptation to repeated restraint.
A single 2 h episode of restraint stress decreased food intake and growth rate of rats. These deficits were not observed after five restraint periods of 2 h a day, suggesting that adaptation occurred. An acute challenge with 2 h restraint increased 5-hydroxytryptamine (5-HT) synthesis rate in the cortex, hypothalamus, midbrain and hindbrain of previously unrestrained rats, but not those adapted to 5 days of 2 h daily restraint. Hippocampal and striatal 5-HT synthesis was not increased significantly by 2 h restraint in previously unrestrained rats but was increased and decreased, respectively, in rats exposed to five 2 h daily restraints, when they were restrained on the sixth day. The findings suggest an important role of 5-HT particularly in the hippocampus, in adaptation to stress.
Haleem
D J
DJ
Department of Biochemistry, University of Karachi, Pakistan.
Parveen
T
T
D006916:5-Hydroxytryptophan / Q000378:metabolism; D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D001923:Brain Chemistry / Q000502:physiology*; D004435:Eating / Q000502:physiology; D006128:Growth / Q000502:physiology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical; D012701:Serotonin / Q000096:biosynthesis*; D013315:Stress, Psychological / Q000378:metabolism*
D012701:Serotonin; D006916:5-Hydroxytryptophan