Abstract
Anxiety and depression, which are fundamental symptoms not only in the psychiatric field but a]so in the whole field of clinical medicine, are reviewed from a neurochemical and neuropharmacological viewpiont, and a few of current topics about these states are introduced briefly. On a basis of the above background a neural mechanism of appearance of depressive state derived from the chronic aversive stress is discussed with focus on the serotoninergic neuronal system, especially on imbalance between 5-HT1 and 5-HT2 subtype serotoninergic system, which is thought to appear from hyperglucocorticoidemia during the chronic stress. Vulnerability to be in this state is thought to depend upon resilience factors of an individual, such as a good social support, a good experience of bringing up by parents, great self-respect etc., and action of these resilience factors is also supposed to control by 5-HT1 neuronal system at hippocampus, which is named as the medial raphe - hippocampal serotoninergic resilience system.
