title: Alterations in arginine vasopressin neurons in the suprachiasmatic nucleus in depression.
abstract: BACKGROUND
  Circadian rhythm disturbances are frequently found in depressed subjects. Although it has been presumed that these disturbances may reflect a disorder of the circadian pacemaker, this has never been established. The suprachiasmatic nucleus (SCN) is the pacemaker of the circadian timing system in mammals, and arginine vasopressin (AVP) is one of its major neuropeptides. As peptide content is often taken as a measure for activity, we hypothesized that a decreased number of AVP-immunoreactive (AVP-IR) neurons and amount of AVP-messenger RNA (mRNA) would be present in the SCN of depressed subjects.
  
  
  METHODS
  Brains of 11 subjects suffering from major depression (8 cases) and bipolar disorder (3 cases), and of 11 controls, matched for sex, age, and clock time at death, were collected. The number of AVP-IR neurons in the SCN was determined by means of a digitizer (CalComp Inc, Reading, England). The amount of AVP-mRNA expression in the SCN was quantified with the Interaktive Bild Analyse System image analysis system (Kontron, Munich, Germany).
  
  
  RESULTS
  In depressed subjects, the number of AVP-IR neurons in the SCN was more than one and a half times higher than in controls, while the total masked area of silver grains, as an estimate of the amount of AVP-mRNA, was about one half that of controls.
  
  
  CONCLUSIONS
  Contrary to our hypothesis, an increase in the number of AVP-IR neurons in the SCN in depression was found, together with an expected decrease in AVP-mRNA. These findings suggest that, in depressed patients, both the synthesis and release of AVP in the SCN is reduced, resulting in an impaired functional ability. A disbalance between AVP production and transport needs further investigation in future studies.
authors.affiliation: Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam, The Netherlands.
authors.forename: J N
authors.initials: JN
authors.lastname: Zhou
authors.forename: R F
authors.initials: RF
authors.lastname: Riemersma
authors.forename: U A
authors.initials: UA
authors.lastname: Unmehopa
authors.forename: W J
authors.initials: WJ
authors.lastname: Hoogendijk
authors.forename: J J
authors.initials: JJ
authors.lastname: van Heerikhuize
authors.forename: M A
authors.initials: MA
authors.lastname: Hofman
authors.forename: D F
authors.initials: DF
authors.lastname: Swaab
mesh_terms: D017668:Age of Onset; D000368:Aged; D001127:Arginine Vasopressin / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D001714:Bipolar Disorder / Q000175:diagnosis / Q000378:metabolism; D002423:Cause of Death; D002452:Cell Count; D002940:Circadian Rhythm / Q000502:physiology; D003866:Depressive Disorder / Q000175:diagnosis / Q000378:metabolism* / Q000401:mortality; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D009474:Neurons / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D013493:Suprachiasmatic Nucleus / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D001127:Arginine Vasopressin