Brain 5-HT function in obsessive-compulsive disorder. Prolactin responses to d-fenfluramine.

BACKGROUND: Drugs that potentiate brain serotonin (5-HT) neurotransmission are effective in the treatment of obsessive-compulsive disorder (OCD), but it is unclear whether disturbances in brain 5-HT function play a role in the pathophysiology of OCD. METHOD: We studied the prolactin response to the selective 5-HT releasing agent d-fenfluramine in 14 non-depressed, drug-free OCD patients, and 14 healthy controls matched for age and gender. RESULTS: The prolactin response to d-fenfluramine was significantly increased in OCD patients compared with controls. CONCLUSIONS: The disparate results of studies of 5-HT neuroendocrine function in OCD make it unlikely that disturbances of brain 5-HT function play a central role in the pathophysiology of OCD. Increased brain 5-HT neurotransmission in non-depressed OCD subjects may represent an adaptive neurobehavioural mechanism which can be amplified to therapeutic advantage by treatment with 5-HT potentiating drugs