L-5-hydroxytryptophan induced increase in salivary cortisol in panic disorder patients and healthy volunteers.
BACKGROUND
Hypersensitivity of brain serotonin receptors has been proposed as a causal mechanism in the pathophysiology of panic disorder. This theory can be tested, using serotonergic stimulation of the HPA axis. Up to now, plasma cortisol has generally been used as the outcome measure in such studies. Assessment of salivary cortisol is a non-invasive alternative to measure HPA axis activity.


METHODS
Salivary cortisol levels were measured in 24 panic disorder patients and 24 healthy volunteers, following ingestion of 200 mg L-5-hydroxytryptophan or placebo.


RESULTS
A significant rise in cortisol was observed in both patients and controls following ingestion of L-5-hydroxytryptophan. No such effects were seen in the placebo condition.


CONCLUSIONS
The results show that L-5-hydroxytryptophan stimulated salivary cortisol is a useful probe of serotonin function in healthy volunteers as well as panic disorder patients, and provide some evidence against a serotonin receptor hypersensitivity in panic disorder.
Schruers
Koen
K
Department of Psychiatry, Institute of Brain and Behaviour, Maastricht University, P.O. Box 88, 6200 AB Maastricht The Netherlands, koen.schruers@pn.unimaas.nl
van Diest
Rob
R
Nicolson
Nancy
N
Griez
Eric
E
D006916:5-Hydroxytryptophan / Q000494:pharmacology*; D000328:Adult; D000704:Analysis of Variance; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D016584:Panic Disorder / Q000378:metabolism*; D012463:Saliva / Q000187:drug effects* / Q000378:metabolism*
D006916:5-Hydroxytryptophan; D006854:Hydrocortisone