New Antidepressant Protein Helps Serotonin Work Better

Current models of depression implicate dysregulation of serotonin neurotransmission, although the nature of the defect is unclear. Serotonin 1B (5-HT_1B) receptors play a crucial role, regulating both the release of serotonin from neurons that contain the neurotransmitter and the action of serotonin at receptors on nonserotonergic neurons. In an elegant and extensive series of animal- and human-tissue studies, researchers identified p11, a novel protein that binds to 5-HT_1B receptors and is anatomically distributed and colocalized with them.

Various antidepressant treatments (imipramine, ECT, and tranylcypromine) increased p11 amounts in rat and mouse cortex. Amounts of p11 were lower in tissue from mice with learned helplessness than from co…