Elevation of cell adhesion molecule immunoreactivity in the anterior cingulate cortex in bipolar disorder

Background Neuroimaging reports of increases in signal hyperintensities in white and deep gray matter and other work indicate that there might be an inflammatory response in affective disorders. Methods The microvascular immunoreactivity of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 was measured with image analysis in postmortem tissue from the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (DLPFC) from 15 unipolar and 15 bipolar subjects and compared with each other and with 15 subjects with schizophrenia and 15 control subjects. Results Intercellular adhesion molecule-1 immunoreactivity in gray and white matter of the ACC in bipolar subjects was increased compared with control subjects (gray: p = .001; white: p< .001) and schizophrenic subjects (gray: p = .016; white: p = .025) and modestly increased in white matter compared with unipolar subjects (p = .049). No such differences were found in the DLPFC. Conclusions These findings are consistent with the presence of an inflammatory response in the ACC in bipolar disorder.