title: PET measurement of the influence of corticosteroids on serotonin-1A receptor number.
abstract: BACKGROUND
  The hypothalamic-pituitary-adrenal (HPA) axis and serotonergic system interact functionally. The modulatory effect of corticosteroids on 5-HT(1A) receptor number and function has been repeatedly demonstrated in preclinical studies suggesting that raised corticosteroid levels decrease 5-HT(1A) receptor number and function in the hippocampus.
  
  
  METHODS
  We used positron emission tomography (PET) to quantify the number of 5-HT(1A) receptors in two studies, the first in normal subjects given a single dose of hydrocortisone using a random-order, double-blind, placebo-controlled design and second in patients treated long-term with corticosteroids.
  
  
  RESULTS
  We did not find that exposure to elevated levels of corticosteroids in either the short or long term alters 5-HT(1A) receptor binding in the hippocampus or other brain regions examined.
  
  
  CONCLUSIONS
  This study does not support the hypothesis that corticosteroids exert a major inhibitory regulatory control over the 5-HT(1A) receptor binding in the human brain.
authors.affiliation: MRC Cyclotron Unit, Imperial College School of Medicine, Charing Cross Hospital, St. Dunstans Road, United Kingdom, London.
authors.forename: A J
authors.initials: AJ
authors.lastname: Montgomery
authors.forename: C J
authors.initials: CJ
authors.lastname: Bench
authors.forename: A H
authors.initials: AH
authors.lastname: Young
authors.forename: A
authors.initials: A
authors.lastname: Hammers
authors.forename: R N
authors.initials: RN
authors.lastname: Gunn
authors.forename: Z
authors.initials: Z
authors.lastname: Bhagwagar
authors.forename: P M
authors.initials: PM
authors.lastname: Grasby
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001667:Binding, Competitive; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000378:metabolism; D006801:Humans; D006854:Hydrocortisone / Q000008:administration & dosage / Q000493:pharmacokinetics*; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010913:Pituitary-Adrenal System / Q000378:metabolism*; D011985:Receptors, Serotonin / Q000378:metabolism*; D044263:Receptors, Serotonin, 5-HT1; D014055:Tomography, Emission-Computed
chemical_list: D000893:Anti-Inflammatory Agents; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D006854:Hydrocortisone