Correlation between cerebral striatal dopamine D 2 receptors non-displaceable binding potential and functional connectivity in patients with major depressive disorder / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To study the correlation between changes of cerebral striatal dopamine D 2 receptors non-displaceable binding potential (BP ND), functional connectivity (FC) and clinical symptoms in patients with first-episode major depressive disorder (MDD), by 11C-Raclopride PET/CT and resting state fMRI (rs-fMRI). Methods:Thirty-eight first-episode depression patients (MDD group) and forty healthy volunteers (control group) matched with age, gender and years of education were selected. All subjects were scored with Hamilton depression scale (24 versions) before enrollment.All the subjects underwent cerebral 11C-Raclopride PET/CT and rs-fMRI in resting state. MIAKAT and DPARSF were used to analyze BP ND of cerebral striatal dopamine D 2 receptors and FC of striatum and the whole brain in subjects, respectively. Changes of striatal dopamine D 2 receptors BP ND and striatum and the whole brain FC of MDD were analyzed, and correlations among BP ND, FC and Hamilton depression rating scale were calculated by Rest 1.8 and SPSS 20.0. Results:Compared with the control group, BP ND of bilateral caudate nucleus and putamen dopamine D 2 receptors in the MDD group were decreased(left caudate nucleus 1.16±0.37 vs 1.48±0.39, right caudate nucleus 1.21±0.31 vs 1.62±0.48, left putamen 1.73±0.47 vs 2.21±0.66, right putamen 1.79±0.46 vs 2.17±0.65, t=3.66, -4.42, -3.68, -2.91, all P<0.001). Besides, FC of left caudate nucleus and left medial prefrontal lobes(4.38±1.31, 2.35±0.48), left caudate nucleus and left middle frontal gyrus(3.36±1.11, 1.64±0.56), left caudate nucleus and left superior frontal gyrus(3.14±0.78, 1.64±0.53), left putamen and left medial prefrontal lobes(4.10±1.42, 2.42±0.64, t=6.82, P<0.05), right caudate nucleus and right medial prefrontal lobes (4.32±1.30, 2.33±0.63, t=8.51, P<0.05), right putamen and right medial prefrontal lobes(3.77±1.25, 2.31±0.63, t=6.49, P<0.05)in the MDD group were increased.FC of left putamen and left anterior cingulate(1.60±0.55, 2.68±0.84, t=-6.76, P<0.05), right caudate nucleus and right amygdala (1.67±0.57, 3.46±0.64, t=-8.27, P<0.05) in the MDD group were decreased. Furthermore, there were significant negative correlations between D 2 receptors BP ND of bilateral striatum and FC of the same lateral striatum and medial prefrontal lobes ( r=-0.66, -0.50, -0.67, -0.47, all P<0.05). In MDD group, FC in left caudate nucleus and left medial prefrontal lobe were positively correlated with total score of Hamilton depression scale and anxiety somatization( r=0.55, 0.68, P<0.001). FC in left putamen and left medial prefrontal cortex were positively correlated with cognitive impairment and retardation ( r=0.37, 0.40, P=0.021, 0.001). FC of right caudate nucleus and right medial prefrontal lobe were positively correlated with Hamilton depression scale total score and anxiety somatization ( r=0.52, 0.67, all P<0.001). FC in right putamen and right medial prefrontal cortex was positively correlated with cognitive impairment ( r=0.50, P=0.002). Conclusion:The abnormal BP ND of cerebral striatal dopamine D 2 receptor of patients with first-episode depression is related to the abnormal activity of dopamine reward circuit related neurons in patients with MDD, which was related to clinical symptoms of depression. It may be involved in the pathogenesis of depression.