title: Nicotine blocks brain estrogen synthase (aromatase): in vivo positron emission tomography studies in female baboons.
abstract: BACKGROUND
  Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase.
  
  
  METHODS
  Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor [(11)C]vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg.
  
  
  RESULTS
  Nicotine administration produced significant, dose-dependent reductions in [(11)C]vorozole binding. The amygdala and preoptic area showed the largest reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers.
  
  
  CONCLUSIONS
  Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior.
authors.affiliation: Brookhaven National Laboratory, Upton, New York, USA. biegon@bnl.gov
authors.forename: Anat
authors.initials: A
authors.lastname: Biegon
authors.forename: Sung-Won
authors.initials: SW
authors.lastname: Kim
authors.forename: Jean
authors.initials: J
authors.lastname: Logan
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Hooker
authors.forename: Lisa
authors.initials: L
authors.lastname: Muench
authors.forename: Joanna S
authors.initials: JS
authors.lastname: Fowler
mesh_terms: D000818:Animals; D047072:Aromatase Inhibitors / Q000493:pharmacokinetics; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects / Q000201:enzymology*; D003627:Data Interpretation, Statistical; D004305:Dose-Response Relationship, Drug; D005260:Female; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology*; D010215:Papio / Q000378:metabolism*; D049268:Positron-Emission Tomography; D014230:Triazoles / Q000493:pharmacokinetics
chemical_list: D047072:Aromatase Inhibitors; D018722:Nicotinic Agonists; D014230:Triazoles; C060523:vorozole; D009538:Nicotine