The American Psychiatric Association (APA) has updated its Privacy Policy and Terms of Use, including with new information specifically addressed to individuals in the European Economic Area. As described in the Privacy Policy and Terms of Use, this website utilizes cookies, including for the purpose of offering an optimal online experience and services tailored to your preferences.

Please read the entire Privacy Policy and Terms of Use. By closing this message, browsing this website, continuing the navigation, or otherwise continuing to use the APA's websites, you confirm that you understand and accept the terms of the Privacy Policy and Terms of Use, including the utilization of cookies.

×
New ResearchFull Access

Lower β2*-Nicotinic Acetylcholine Receptor Availability in Smokers With Schizophrenia

Objective:

There is a strong association between cigarette smoking and schizophrenia. Nicotine's actions in the brain are mediated through nicotinic acetylcholine receptors. Those containing α4 and β2 subunits are the most abundant ones in the brain, have the highest affinity for nicotine, and are critical in mediating nicotine's reinforcing properties. Healthy tobacco smokers have significantly higher levels of β2*-nicotinic acetylcholine receptors than do nonsmokers. However, in postmortem studies, smokers with schizophrenia do not show these higher levels. The purpose of this study was to measure β2*-nicotinic acetylcholine receptors in vivo and to relate levels to concurrent behavioral measures of smoking and schizophrenia.

Method:

By using single-photon emission computed tomography with the β2*-nicotinic acetylcholine receptor agonist radiotracer [123I]5-IA-85380, the availability of receptors was measured in smokers with schizophrenia (11 men) and matched comparison smokers after 1 week of confirmed smoking abstinence.

Results:

Smokers with schizophrenia showed significantly lower (21%–26%) β2*-nicotinic acetylcholine receptor availability relative to comparison smokers in the frontal cortex, parietal cortex, and thalamus (in descending order). There was a specific and robust negative correlation between regional β2*-nicotinic acetylcholine receptor availability and negative symptoms.

Conclusions:

These are the first in vivo findings of lower β2*-nicotinic acetylcholine receptor availability in smokers with schizophrenia. The relationship between β2*-nicotinic acetylcholine receptor availability and negative symptoms may explain the high rates of smoking in schizophrenia and the relationship between smoking and negative symptoms. Findings support the development of medications targeting the β2*-nicotinic acetylcholine receptor system for the treatment of negative symptoms.