Cytokines, Stress, and Depressive Illness

Stressors may instigate a series of hormonal variations, coupled with neurochemical alterations within the brain that promote cognitive alterations and favor the development of depressive illness. Indeed, it appears that in many respects the effects of stressors are reminiscent of the presumed neurochemical disturbances thought to be associated with depression, including elevated hypothalamic-pituitary-adrenal (HPA) functioning, as well as altered monoamine activity within hypothalamic and limbic areas of the brain. With respect to the latter, it has become clear that stressors reliably induce variations of brain norepinephrine (NE), dopamine (DA), and serotonin (5-HT) and that the behavioral disturbances associated with stressors are alleviated by treatments that attenuate the amine alterations, including antidepressant agents (1 ).