title: Elevated brain monoamine oxidase A binding in the early postpartum period.
abstract: BACKGROUND
  The early postpartum period is a time of high risk for a major depressive episode (or postpartum depression), with a prevalence of 13%. During this time, there is a heightened vulnerability for low mood because postpartum blues is common. Severe postpartum blues can herald the onset of postpartum depression. The neurobiological mechanisms to explain postpartum blues and the high risk for the onset of postpartum depression in the first few weeks after delivery are unclear. Estrogen levels drop 100- to 1000-fold during the first 3 to 4 days postpartum, and changes in estrogen levels have an inverse relationship with monoamine oxidase A (MAO-A) density. However, MAO-A levels have never been measured in the early postpartum period.
  
  
  OBJECTIVE
  To determine whether brain MAO-A binding is elevated in the early postpartum period.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Tertiary care academic psychiatric hospital in Toronto, Ontario, Canada.
  
  
  METHODS
  Fifteen healthy women who were 4 to 6 days postpartum and 15 healthy women who had not recently been postpartum underwent carbon 11-labeled harmine positron emission tomography scanning. All women were nonsmoking and medication free.
  
  
  METHODS
  MAO-A total distribution volume, an index of MAO-A density, was measured in prefrontal cortex, anterior cingulate cortex, anterior temporal cortex, thalamus, dorsal putamen, hippocampus, and midbrain.
  
  
  RESULTS
  MAO-A total distribution volume was significantly elevated (mean, 43%) throughout all analyzed brain regions during the early postpartum period.
  
  
  CONCLUSIONS
  Elevated MAO-A levels in the early postpartum period can be interpreted as a marker of a monoamine-lowering process that contributes to the mood change of postpartum blues. Rather than a purely psychosocial model, we propose a neurobiological model of estrogen decline, followed by elevated MAO-A binding, low mood, and subsequently a period of high risk for major depressive episodes. Our model has important implications for preventing postpartum depression and for developing therapeutic strategies that target or compensate for elevated MAO-A levels during postpartum blues.
authors.affiliation: Vivian M. Rakoff PET Centre, Centre for Addiction and Mental Health and Department of Psychiatry, University of Toronto, Toronto, Ontario M5T 1R8, Canada.
authors.forename: Julia
authors.initials: J
authors.lastname: Sacher
authors.forename: Alan A
authors.initials: AA
authors.lastname: Wilson
authors.forename: Sylvain
authors.initials: S
authors.lastname: Houle
authors.forename: Pablo
authors.initials: P
authors.lastname: Rusjan
authors.forename: Sabrina
authors.initials: S
authors.lastname: Hassan
authors.forename: Peter M
authors.initials: PM
authors.lastname: Bloomfield
authors.forename: Donna E
authors.initials: DE
authors.lastname: Stewart
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Meyer
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000201:enzymology*; D002250:Carbon Radioisotopes; D016022:Case-Control Studies; D019052:Depression, Postpartum / Q000000981:diagnostic imaging / Q000201:enzymology*; D003865:Major Depressive Disorder / Q000000981:diagnostic imaging / Q000201:enzymology*; D004958:Estradiol / Q000378:metabolism; D005260:Female; D006247:Harmine; D006801:Humans; D008995:Monoamine Oxidase / Q000378:metabolism*; D049268:Positron-Emission Tomography; D012016:Reference Values
chemical_list: D002250:Carbon Radioisotopes; D006247:Harmine; D004958:Estradiol; D008995:Monoamine Oxidase