Stimulatory effects of L-5-hydroxytryptophan on postdexamethasone beta-endorphin levels in major depression.
Recently it has been shown that acute administration of 200 mg L-5-hydroxytryptophan (L-5-HTP) PO may increase post-dexamethasone (DST) adrenocorticotropic hormone (ACTH) and cortisol levels in major, but not minor, depressed subjects. This study aimed to examine the effects of 200 mg L-5-HTP PO on post-DST beta-endorphin levels in the same depressed subjects. It was found that in major, but not minor, depressed subjects, L-5-HTP significantly increased post-DST beta-endorphin concentrations as compared to placebo. The L-5-HTP-induced post-DST beta-endorphin responses were significantly higher in major than in minor depressed subjects. There was a significant and positive relationship between L-5-HTP-induced post-DST beta-endorphin and ACTH or cortisol responses. There was a significant and positive relationship between L-5-HTP-induced post-DST beta-endorphin values and the Hamilton Depression Rating Scale (HDRS) score. The results show that the acute administration of L-5-HTP may increase the escape of beta-endorphin secretion from suppression by dexamethasone in major, but not minor, depression.
University Department of Psychiatry, AZ Stuivenberg, Belgium.
M
M
Maes
A
A
Van Gastel
R
R
Ranjan
P
P
Blockx
P
P
Cosyns
H Y
HY
Meltzer
R
R
Desnyder
D000328:Adult; D003866:Depressive Disorder / Q000188:drug therapy* / Q000378:metabolism; D003907:Dexamethasone / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012701:Serotonin / Q000627:therapeutic use*; D001615:beta-Endorphin / Q000378:metabolism*
D012701:Serotonin; D001615:beta-Endorphin; D003907:Dexamethasone