Plasma oxytocin in response to pharmaco-challenge to D-fenfluramine and placebo in healthy men.
The neuropeptide oxytocin is produced in the hypothalamus and released centrally and peripherally in response to serotonergic stimulation. Plasma oxytocin levels may be a candidate as a biological index of serotonergic function in response to pharmacological challenge by serotonergic agents. Fourteen male healthy subjects underwent a placebo challenge and a D-fenfluramine (D-FEN) (0.5 mg/kg) challenge on different days. Serial plasma oxytocin and prolactin levels were measured on each challenge day. D-FEN was associated with an increase in both oxytocin and prolactin. Plasma oxytocin may function as an index of central serotonin (5-HT) function in human subjects. Since oxytocin is released directly from limbic-hypothalamic cells, this response presumably represents a direct central assessment of 5-HT response in limbic-hypothalamus. Further work will determine if the oxytocin response to 5-HT pharmaco-challenge, by virtue of its central origin, is more highly related to measures of psychopathology (e.g. aggression) than that of less central outcome parameters of 5-HT responsiveness (e.g. prolactin).
Lee
Royce
R
Clinical Neuroscience and Psychopharmacology Research Unit, Department of Psychiatry (MC#3077), Pritzker School of Medicine, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA. rlee@yoda.bsd.uchicago.edu
Garcia
Francisca
F
van de Kar
Louis D
LD
Hauger
Richard D
RD
Coccaro
Emil F
EF
D000328:Adult; D001519:Behavior / Q000187:drug effects; D015415:Biomarkers / Q000097:blood; D005277:Fenfluramine / Q000494:pharmacology*; D006801:Humans; D008297:Male; D010121:Oxytocin / Q000097:blood* / Q000187:drug effects*; D011388:Prolactin / Q000097:blood / Q000187:drug effects; D012016:Reference Values; D012701:Serotonin / Q000097:blood; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*; D013997:Time Factors
D015415:Biomarkers; D005277:Fenfluramine; D010121:Oxytocin; D011388:Prolactin; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors