Our laboratory investigates the mechanism of selective secretion of cytokines and other pro-inflammatory molecules from mast cells. We have shown for the first time that mast cells can be activated by corticotropin-releasing hormone (CRH), the first molecule generated under stress, and by interleukin-1. CRH-activated mast cells lead to disruption of the gut-blood-brain barriers and thus contribute to brain inflammation. This process may participate in the pathophysiology of many diseases that worsen or precipitate under stress.