Increased orexin levels in the cerebrospinal fluid the first year after a suicide attempt.
BACKGROUND
The orexins (hypocretins) and cocaine and amphetamine regulated transcript (CART) are hypothalamic peptides involved in the regulation of sleep and appetite. We have previously shown that levels of both orexin-A and CART in the cerebrospinal fluid (CSF) are related to specific psychiatric symptoms.


METHODS
Ten patients took part in lumbar punctures and psychiatric evaluations in conjunction to a suicide attempt and after 6 and 12 months. We measured CSF-orexin and CART using radioimmunoassays.


RESULTS
Mean CSF-orexin was significantly higher at the first and second follow-up than at the suicide attempt. In contrast, mean CSF-CART did not differ over time. Total SUAS scores, as well as ratings of CPRS item 66 (global illness) were significantly lower at follow-up. At one year, there was a significant negative correlation between the change in CSF-orexin and the change in total SUAS score.


CONCLUSIONS
The number of patients who participated was relatively small.


CONCLUSIONS
Our results support the hypothesis that orexin is involved in psychiatric symptomatology.
Division of Psychiatry, Department of Clinical Sciences, Lund University, Lund, Sweden. Lena.Brundin@med.lu.se
Lena
L
Brundin
Maria
M
Björkqvist
Lil
L
Träskman-Bendz
Asa
A
Petersén
D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000134:cerebrospinal fluid*; D008297:Male; D009419:Nerve Tissue Proteins / Q000134:cerebrospinal fluid* / Q000378:metabolism; D009479:Neuropeptides / Q000134:cerebrospinal fluid*; D000068797:Orexins; D011863:Radioimmunoassay; D013406:Suicide, Attempted / Q000523:psychology*; D013997:Time Factors; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
C000596229:HCRT protein, human; D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D000068797:Orexins; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein