Vulnerability of conditional NCAM-deficient mice to develop stress-induced behavioral alterations

Previous studies in rodents showed that chronic stress induces structural and functional alterations in several brain regions, including shrinkage of the hippocampus and the prefrontal cortex, which are accompanied by cognitive and emotional disturbances. Reduced expression of the neural cell adhesion molecule (NCAM) following chronic stress has been proposed to be crucially involved in neuronal retraction and behavioral alterations. Since NCAM gene polymorphisms and altered expression of alternatively spliced NCAM isoforms have been associated with bipolar depression and schizophrenia in humans, we hypothesized that reduced expression of NCAM renders individuals more vulnerable to the deleterious effects of stress on behavior. Here, we specifically questioned whether mice in which the NCAM gene is inactivated in the forebrain by cre-recombinase under the control of the calcium–calmodulin-dependent kinase II promoter (conditional NCAM-deficient mice), display increased vulnerability to stress. We assessed...