Arches. Photo by Daniel Chia
HOPES: Huntington's Outreach Project for Education, at Stanford
Feb
07
2011

HPA axis

The hypothalamic-pituitary-adrenal axis (HPA axis) is a major part of the neuroendocrine system that controls reactions to stress. Species from humans to the most ancient organisms share components of the HPA axis. It is the mechanism for a set of interactions among glands, hormones and parts of the mid-brain that mediate a stress reaction.