Antidepressant-like behavior in brain-specific angiogenesis inhibitor 2-deficient mice.

Brain-specific angiogenesis inhibitor 2 (BAI2) is a transmembrane protein that is predominantly expressed in the brain. Although BAI2 is supposed to correlate with antiangiogenesis in the brain, its psychiatric function is still unclear. In this study, we examined the influence of BAI2 gene disruption on mood-related behavior using BAI2-deficient mice. BAI2-deficient mice showed significant antidepressant-like behavior in the social defeat test and in the tail suspension test compared with wild-type mice. On the other hand, BAI2-deficient mice had normal basal locomotor activity in the home cage and in the open field test, and normal learning ability and memory retention in the Morris water maze test. Additionally, we found that hippocampal cell proliferation in BAI2-deficient mice was higher than that in wild-type mice. These results indicate that BAI2 has an important role related to depression and influences the hippocampal neurogenesis. BAI2 may be a novel therapeutic target for mood-related disorders.