Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2008-4-18
pubmed:abstractText
Considerable attention has focused on regulation of central tryptophan hydroxylase (TPH) activity and protein expression. At the time of these earlier studies, it was thought that there was a single central TPH isoform. However, with the recent identification of TPH2, it becomes important to distinguish between regulatory effects on the protein expression and activity of the two isoforms. We have generated a TPH2-specific polyclonal antiserum (TPH2-6361) to study regulation of TPH2 at the protein level and to examine the distribution of TPH2 expression in rodent and human brain. TPH2 immunoreactivity (IR) was detected throughout the raphe nuclei, in lateral hypothalamic nuclei and in the pineal body of rodent and human brain. In addition, a prominent TPH2-IR fiber network was found in the human median eminence. We recently reported that glucocorticoid treatment of C57/Bl6 mice for 4 days markedly decreased TPH2 messenger RNA levels in the raphe nuclei, whereas TPH1 mRNA was unaffected. The glucocorticoid-elicited inhibition of TPH2 gene expression was blocked by co-administration of the glucocorticoid receptor antagonist mifepristone (RU-486). Using TPH2-6361, we have extended these findings to show a dose-dependent decrease in raphe TPH2 protein levels in response to 4 days of treatment with dexamethasone; this effect was blocked by co-administration of mifepristone. Moreover, the glucocorticoid-elicited inhibition of TPH2 was functionally significant: serotonin synthesis was significantly reduced in the frontal cortex of glucocorticoid-treated mice, an effect that was blocked by mifepristone co-administration. This study provides further evidence for the glucocorticoid regulation of serotonin biosynthesis via inhibition of TPH2 expression, and suggest that elevated glucocorticoid levels may be relevant to the etiology of psychiatric diseases, such as depression, where hypothalamic-pituitary-adrenal axis dysregulation has been documented.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/5-Hydroxytryptophan, http://linkedlifedata.com/resource/pubmed/chemical/Dexamethasone, http://linkedlifedata.com/resource/pubmed/chemical/Immune Sera, http://linkedlifedata.com/resource/pubmed/chemical/Mifepristone, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments, http://linkedlifedata.com/resource/pubmed/chemical/Protein Isoforms, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/TPH2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Tph2 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Tryptophan Hydroxylase, http://linkedlifedata.com/resource/pubmed/chemical/dexamethasone acetate
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1476-5578
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
498-506
pubmed:meshHeading
pubmed-meshheading:17622221-5-Hydroxytryptophan, pubmed-meshheading:17622221-Amino Acid Sequence, pubmed-meshheading:17622221-Animals, pubmed-meshheading:17622221-Antibody Specificity, pubmed-meshheading:17622221-Dexamethasone, pubmed-meshheading:17622221-Enzyme Induction, pubmed-meshheading:17622221-Female, pubmed-meshheading:17622221-Frontal Lobe, pubmed-meshheading:17622221-Humans, pubmed-meshheading:17622221-Immune Sera, pubmed-meshheading:17622221-Mice, pubmed-meshheading:17622221-Mice, Inbred C57BL, pubmed-meshheading:17622221-Mifepristone, pubmed-meshheading:17622221-Molecular Sequence Data, pubmed-meshheading:17622221-Nerve Tissue Proteins, pubmed-meshheading:17622221-Ovariectomy, pubmed-meshheading:17622221-Peptide Fragments, pubmed-meshheading:17622221-Protein Isoforms, pubmed-meshheading:17622221-RNA, Messenger, pubmed-meshheading:17622221-Raphe Nuclei, pubmed-meshheading:17622221-Rats, pubmed-meshheading:17622221-Rats, Sprague-Dawley, pubmed-meshheading:17622221-Tryptophan Hydroxylase
pubmed:year
2008
pubmed:articleTitle
Glucocorticoid modulation of tryptophan hydroxylase-2 protein in raphe nuclei and 5-hydroxytryptophan concentrations in frontal cortex of C57/Bl6 mice.
pubmed:affiliation
Stroke and Neurodegeneration, Merck Research Laboratories, West Point, PA 19486, USA. janet_clark@merck.com
pubmed:publicationType
Journal Article, Research Support, N.I.H., Intramural