Corticotropin-releasing hormone, arginine vasopressin, gastrin-releasing peptide, and neuromedin B alterations in stress-relevant brain regions of suicides and control subjects.
BACKGROUND
Postmortem levels of several stress- and depression-relevant neuropeptides were assessed in brain regions of depressed suicides relative to control subjects that had died of other causes.


METHODS
Brains of suicides and those that died from other causes were collected soon after death (typically <6 hours). Immunoreactivity levels (ir) of corticotropin-releasing hormone (CRH-ir) and arginine vasopressin (AVP-ir), and the bombesin analogs, gastrin-releasing peptide (GRP-ir), and neuromedin B (NMB-ir), were assessed.


RESULTS
Levels of CRH-ir among suicides were elevated in the locus coeruleus (LC), frontopolar, dorsolateral prefrontal (DMPFC) and ventromedial prefrontal cortices, but were reduced at the dorsovagal complex (DVC). The concentration of AVP-ir was elevated at the paraventricluar hypothalamic nucleus, LC, and DMPFC, and reduced at the DVC. Finally, GRP and NMB variations, which might influence anxiety states, were limited, although GRP-ir within the LC of suicides was higher than in control subjects, while NMB-ir was reduced at the DVC of suicides.


CONCLUSIONS
The data show several neuropeptide changes in relation to suicide, although it is premature to ascribe these outcomes specifically to the suicide act versus depression. Likewise, it is uncertain whether the neuropeptide alterations were etiologically related to suicide/depression or secondary to the depressive state.
Merali
Zul
Z
Institute of Mental Health Research, University of Ottawa, Ontario, Canada. merali@uottawa.ca
Kent
Pamela
P
Du
Lisheng
L
Hrdina
Pavel
P
Palkovits
Miklos
M
Faludi
Gabor
G
Poulter
Michael O
MO
Bédard
Tania
T
Anisman
Hymie
H
D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D001127:Arginine Vasopressin / Q000378:metabolism*; D001714:Bipolar Disorder / Q000378:metabolism*; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D003865:Major Depressive Disorder / Q000378:metabolism*; D005260:Female; D019886:Gastrin-Releasing Peptide / Q000378:metabolism*; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015287:Neurokinin B / Q000031:analogs & derivatives* / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D010913:Pituitary-Adrenal System / Q000378:metabolism; D011863:Radioimmunoassay; D013405:Suicide / Q000523:psychology*
D001127:Arginine Vasopressin; D019886:Gastrin-Releasing Peptide; D015287:Neurokinin B; C038393:neuromedin B; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone