OBJECTIVE: To explore the correlation between altered levels of neurotransmitters in the frontal lobe and hippocampus and behavioral abnormalities in a Clock variant mice modeling bipolar disorder manic disorder. METHODS: Open field test and Elevated plus-maze test were carried out on the Clock mutant and wild-type control groups. The frontal lobe and hippocampus of Clock mutant mice and controls were dissected, and neurotransmitters in tissue extracts were analyzed by high-performance liquid chromatography and mass spectrometry. The concentration of neurotransmitters and behavioral indicators were assessed by t test and Pearson correlation analysis using SPSS 22.0. RESULTS: The Clock mutant mice showed a significant increase in activity, albeit with no difference in the level of anxiety from the wild-type controls, which suggested that the Clock mutant mice can be used as a model for manic attack of bipolar disorder. Altered neurotransmitter levels were detected in the frontal and hippocampal regions, including elevated histamine in the left hippocampus, reduced histamine in the right hippocampus, reduced gamma-aminobutyric acid (GABA) in bilateral hippocampus, elevated dihydroxyphenylalanine (DOPA) in the left frontal lobe and reduced DOPA in the right hippocampus, and decreased glutamine in bilateral frontal lobes. The reduced glutamine in the left frontal lobe and GABA in the right hippocampus correlated with the increased activity of Clock mutant mice. CONCLUSION Clock mutant mice showed abnormal behavior with increased activity. Reduced glutamine in the left frontal lobe and GABA in the right hippocampus were correlated with increased activity.

Humans ; Depressive Disorder, Major ; Motor Cortex ; Magnetic Resonance Imaging