Decreased 5-HT1A receptor binding in amygdala of schizophrenia.

BACKGROUND: On the basis of postmortem data and the pharmacological action of atypical antipsychotics, serotonin-1A receptors are of interest in the study of the pathophysiology of schizophrenia. To investigate serotonin-1A receptors in schizophrenia and their relation to symptoms, we measured the availability of serotonin-1A receptors in patients with schizophrenia using positron emission tomography with [carbonyl-(11)C]WAY-100635. METHODS: Serotonin-1A receptor binding of 11 patients with schizophrenia (8 drug-naive and 3 drug-free) was compared with that of 22 age-matched and gender-matched healthy control subjects. Symptoms were assessed using the Positive and Negative Syndrome Scale. Serotonin-1A receptor binding in selected regions of interest was quantified by binding potential obtained by the reference tissue method. RESULTS: The regional binding potential value was lower in the amygdala by about 19% in patients with schizophrenia than in normal controls. A significant negative correlation was observed between binding potential in the amygdala and the negative and depression/anxiety symptom scores on the five-symptom subscale of the Positive and Negative Syndrome Scale. CONCLUSIONS: Decreased serotonin-1A receptor binding in the amygdala may underlie the affective components included in the symptoms of negative and depression/anxiety in schizophrenia.