Certain adrenal hormones are released in response to stress. They reduce the proliferation of dentate gyrus progenitor cells in the adult hippocaptus . Many corticosteroids reduce the formation of granular nerve cells by inhibiting stem cell division.
NMDA receptors are involved in the realization of the effects of corticosteroids, their blockade prevents the negative effects of corticosteroids. Any violation of neurogenesis develops depression. The hippocampus and prefrontal area may atrophy in depressed patients. When treated with fluoxetine, an antidepressant, the content of new cells in the dentate gyrus increases, and inhibition of serotonin synthesis leads to a decrease in the processes of neurogenesis in the hippocampus .
The microstructure of the hippocampus changes with irradiation, which also leads to an increase in the functioning of microglia and changes in vascularization .