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Signal Attenuation as a Rat Model of Obsessive Compulsive Disorder
Published on: January 9, 2015
Effects of catecholamine depletion with AMPT (alpha-methyl-para-tyrosine) in obsessive-compulsive disorder
J G Longhurst1, L L Carpenter, C N Epperson
1Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut, USA.
Background:
Several lines of evidence suggest that brain dopamine function may contribute to some obsessive-compulsive (OC) phenomena. The effects of catecholamine depletion were examined in drug-free patients with obsessive-compulsive disorder (OCD).
Methods:
The tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine (AMPT) and diphenhydramine hydrochloride (placebo) were administered for three consecutive days, one week apart, to 6 drug-free adult OCD patients without a personal or family history of chronic tics, in a double-blind, randomized design. The effects of AMPT and placebo on OC, depression, anxiety and global clinical symptoms were assessed.
Results:
AMPT produced no clinically or statistically significant change in any behavioral ratings, including OC symptom severity, compared with placebo.
Conclusions:
Acute reduction of catecholamine levels does not seem to affect OC symptoms in drug-free patients with OCD. Studies of catecholamine depletion with AMPT in patients with comorbid OCD and chronic tics may be of considerable neurobiological and clinical interest.
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