The contribution of orbitofrontal cortex to stress-related psychiatric disorders: stress induced synaptic change in the orbitofrontal-basolateral amygdala pathway

Abstract

Exposure to stress induces alterations in synaptic functions, and increases the risk of stress-related psychiatric disorders, such as major depression and PTSD. To develop new treatments for stress-related psychiatric disorders, it is important to understand the effect of stress on the emotional circuits, such as prefrontal cortex (PFC), amygdala and other limbic regions. The orbitofrontal cortex (OFC, ventral subregion of the PFC) has important roles for processing of negative emotion and has recently been highlighted as a critical region in stress-related psychiatric disorders. However, mechanisms how stress affect OFC circuit and induce psychiatric symptoms were less understood. OFC sends dense projection to the amygdala, which is one of the key nodes for processing of negative emotion. Taken together, there is a possibility that stress affects the information processing in the OFC-amygdala pathway, and it underlies stress-induced emotional alteration. In this article, we introduce our research that examined effects of stress on the excitatory synaptic transmission from OFC to the basolateral nucleus of the amygdala (BLA) using optogenetic and whole-cell patch-clamp methods in mice.