More Insight into the Pathophysiology of Bipolar Disorder

Bipolar disorder is associated with greater intracellular calcium ion (Ca²⁺) signaling in peripheral cells such as platelets and lymphocytes. This widely replicated finding may be associated with enhanced Ca²⁺ release from intracellular stores. Lithium attenuates hyperactive Ca²⁺ signaling and induces the gene for the antiapoptotic protein Bcl-2, which is down-regulated in bipolar disorder and which interacts with the receptor on the endoplasmic reticulum (ER) and other intracellular Ca²⁺ storage sites that release Ca²⁺. To examine whether differentially active single nucleotide polymorphisms (SNPs) in the Bcl-2 gene contribute to excessive mobilization of intracellular Ca²⁺, researchers studied lymphoblast cell lines cultured from 18 patie…