Plasma prolactin response to D-fenfluramine is blunted in bulimic patients with frequent binge episodes.
BACKGROUND
Abnormalities of brain serotonin (5-HT) transmission have been implicated in the pathophysiology of bulimia nervosa (BN), but no conclusive data have yet been provided. The purpose of this study was to assess 5-HT transmission via the measurement of the prolactin (PRL) response to the specific 5-HT releasing agent D-fenfluramine (D-FEN) in both patients with BN and comparison subjects.


METHODS
According to a double-blind placebo-controlled design, plasma PRL response to D-FEN was measured in 14 drug-free bulimics and 14 matched healthy controls. In both patients and controls, eating-related psychopathology, depressive and obsessive-compulsive symptoms, and aggressiveness were measured by rating scales.


RESULTS
Baseline plasma levels of PRL and 17 beta-oestradiol were significantly reduced in bulimic patients, whereas basal plasma levels of cortisol did not significantly differ from healthy controls. PRL response to D-FEN was not different between patients and controls as groups, but it was significantly blunted in bulimics with high frequency bingeing (> or = 2 binge episodes per day; N = 7) as compared to both those with low frequency bingeing (< or = 1 binge episode per day; N = 7) and matched controls. A significant negative correlation emerged between the frequency of binge episodes and the hormone response to D-FEN. Moreover, although patients scored higher than healthy subjects on rating scales assessing depressive and obsessive-compulsive symptoms and aggressiveness, no significant correlation was found between these measures and the PRL response to D-FEN.


CONCLUSIONS
These results support the idea that serotonin transmission is impaired in bulimic patients with frequent binge episodes.
Monteleone
P
P
Institute of Psychiatry, School of Medicine, University of Naples SUN, Italy.
Brambilla
F
F
Bortolotti
F
F
Ferraro
C
C
Maj
M
M
D000328:Adult; D002032:Bulimia / Q000503:physiopathology*; D004311:Double-Blind Method; D005260:Female; D005277:Fenfluramine / Q000494:pharmacology*; D006801:Humans; D008297:Male; D011388:Prolactin / Q000097:blood*; D011569:Psychiatric Status Rating Scales; D018490:Serotonin Agents / Q000494:pharmacology*
D018490:Serotonin Agents; D005277:Fenfluramine; D011388:Prolactin