The limbic–hypothalamic–pituitary–adrenal axis.

The structures involved in this system include: the hippocampus, periventricular nucleus (PVN) of the hypothalamus, the anterior pituitary and the adrenal gland. Inhibition of the stress response is accomplished by three mechanisms: rate sensitive feedback, intermediate feedback and delayed feedback.

GR, glucocorticoid receptor; MR, mineralocorticoid receptor;

CRH, corticotropin releasing hormone; AVP, vasopressin;

POMC, proopiomelanocortin; ACTH, adrenocorticotropin;

hnmRNA, heteronuclear mRNA; pm, posterior magnocellular PVN;

mp, medial parvocellular PVN; ME, median eminence;

al, anterior lobe; il, intermediate lobe; nl, neural lobe;

ctx, cortex; and med, medulla.