Abstract
Repeated stress triggers a wide range of adaptive changes in the central nervous system including the elevation of serotonin (5-HT) metabolism and an increased susceptibility to affective disorders. To begin to examine whether these changes are mediated by alterations in gene expression for tryptophan hydroxylase (TPH), the rate-limiting enzyme in 5-HT biosynthesis, we quantitated its mRNA levels by competitive reverse transcription-polymerase chain reaction (RT-PCR). Repeated immobilization stress (2 h, 7 days) elicited a six- or ten-fold rise in TPH mRNA in median raphe nucleus (MRN) and dorsal raphe nucleus (DRN), respectively, without significantly altering TPH mRNA levels in the pineal gland. In contrast, there was little change in mRNA levels for GTP cyclohydrolase I (GTPCH), the rate limiting enzyme in synthesis of the tetrahydrobiopterin (BH4), the obligate cofactor for TPH. This is the first study to reveal stress-elicited activation of TPH gene expression.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
