• To evaluate serotonergic (5-hydroxytryptamine) function in obsessive-compulsive disorder, behavioral and neuroendocrine responses to m-chlorophenylpiperazine (m-CPP; 0.5 mg/kg orally) and fenfluramine hydrochloride (60 mg orally) were examined in 20 patients and 10 healthy controls under double-blind, placebo-controlled conditions. Following m-CPP, but not fenfluramine or placebo, 55% (11/20) of the patients with obsessive-compulsive disorder experienced a transient exacerbation of obsessivecompulsive disorder. Prolactin response was blunted in patients following m-CPP but not following fenfluramine. Patients with greater behavioral response to m-CPP had smaller prolactin responses. Cortisol response to m-CPP and fenfluramine did not significantly differ between the groups. Behavioral and neuroendocrine responses appeared divergent. This does not suggest simply upregulation or downregulation of 5-hydroxytryptamine receptors, but rather complex mechanisms involving multiple neurotransmitter and neuromodulator systems.
Hollander E, DeCaria CM, Nitescu A, Gully R, Suckow RF, Cooper TB, Gorman JM, Klein DF, Liebowitz MR. Serotonergic Function in Obsessive-Compulsive DisorderBehavioral and Neuroendocrine Responses to Oral m-Chlorophenylpiperazine and Fenfluramine in Patients and Healthy Volunteers. Arch Gen Psychiatry. 1992;49(1):21-28. doi:10.1001/archpsyc.1992.01820010021003