HPA STRESS AXIS AND SEROTONIN IN MAJOR DEPRESSION
		• Hypothalamic Pituitary Adrenal Axis (HPA) overactivity (elevated CRH and cortisol, dexamethasone resistance) is present in many patients with severe depression. • Corticosteroids reduce hippocampal 5-HT1A receptor sites in animal studies and may explain reduced hippocampal damage in depression.