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 obsess ive 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-HTreleasing 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 nondepressed OCD subjects may represent an adaptive neurobehavioural mechanism which can be amplified to therapeutic advantage by treatment with 5-HT potentiating drugs.