Multi-modal imaging study of striatal dopamine D2receptors binding potential and brain regional homogeneity in patients with first-episode major depressive disorder / 中华放射学杂志

ABSTRACT

Objective To explore the correlation between changes of striatal dopamine D2receptors non-displaceable binding potential (BPND) in 11C-Raclopride PET-CT and brain regional homogeneity (ReHo) derived from resting state functional MRI (fMRI) in patients with first-episode major depressive disorder (MDD) . Methods Patients with first-episode MDD and age and sex matched healthy volunteers accepted brain 11C-Raclopride PET-CT and resting state fMRI. MIAKAT based on MATLAB and Rest 1.8 were used to calculate BPNDof brain dopamine D2receptors and brain ReHo, respectively. Changes of striatal dopamine D2receptors BPNDand brain ReHo values were analyzed by paired-sample t test and two independent sample t-test, and Pearson correlation analysis was used to analyze the correlation between BPNDand ReHo. Results Twenty patients with first-episode MDD were enrolled as MDD group, and 20 healthy volunteers as the control group. The two groups were all right-handed, and there were no statistical differences for age (t =1.33,P=0.19)and gender(χ2=0.10,P=0.75). Compared with the control group, the ReHo in MDD patients increased in the bilateral striatum (caudate nucleus and putamen), bilateral medial prefrontal lobes, and right thalamic (27 to 56 voxels, P＜0.05) and decreased in the left middle frontal gyrus, the left anterior cingulate, the left hippocampal and the right amygdala (21 to 35 voxels, P＜0.05). In addition, compared with the control group, BPNDof bilateral caudate nucleus and putamen dopamine D2receptors in the MDD group were decreased (t=－4.41 to －3.13, P＜0.05). Furthermore, there was a negative correlation between D2 receptors BPNDand ReHo of bilateral caudate nucleus and putamen (r=－0.81 to－0.62, P＜0.05). And there was a negative correlation between ReHo of the bilateral medial prefrontal lobes and BPNDof the same lateral caudate nucleus and putamen D2receptors in the MDD group (r=－0.86 to－0.52, P＜0.05). Besides, ReHo of the left middle frontal gyrus, right thalamic, left anterior cingulate, left hippocampal and right amygdala had no correlation with the D2receptors BPNDof the striatum in the MDD group (－0.27 to 0.39, P＞0.05). Conclusion There were abnormal levels of dopamine neurotransmitter in the cerebral striatum regions and abnormal brain activities in the brain region associated with dopamine reward circuit in the first-episode MDD patients, and there was a correlation between the two abnormalities.