Role of serotonin in obsessive-compulsive disorder

Area of Science:

• Neuroscience
• Psychiatry
• Pharmacology

Background:

• Selective serotonin reuptake inhibitors (SSRIs) show anti-obsessional effects, suggesting serotonin's role in obsessive-compulsive disorder (OCD) pathophysiology.
• Understanding the neurobiological underpinnings of OCD is crucial for developing effective treatments.

Purpose of the Study:

• To review the literature on the role of serotonergic neurons in brain function and their relation to OCD.
• To investigate the impact of SSRIs on neurochemical and neuropeptide alterations in OCD.

Main Methods:

• Literature review encompassing serotonergic neuron function, cerebrospinal fluid (CSF) monoamine metabolites, stress neuropeptides, and neuroanatomical data.
• Analysis of studies on neuroendocrine and behavioral challenges with serotomimetic compounds.

Main Results:

• CSF 5-hydroxyindoleacetic acid and homovanillic acid levels generally do not differ significantly in OCD patients compared to controls.
• Pre-treatment metabolite levels correlate with clinical response to serotonin transporter-acting drugs.
• OCD patients exhibit abnormalities in CSF arginine vasopressin, corticotropin-releasing hormone, oxytocin, and somatostatin, which are corrected by long-term SSRI treatment.

Conclusions:

• Continuous SSRI treatment is hypothesized to modify serotonin turnover and neuropeptide expression in relevant brain circuits in OCD.
• SSRI therapy may normalize neuropeptide dysregulation associated with obsessive-compulsive disorder.