The Human Stress Response: The Roles of CRH, ACTH, Adrenaline, Cortisol, and Glucocorticoids
The human body's response to stress is one of its most sophisticated survival mechanisms. Whether the threat is physical, emotional, or psychological, the body rapidly activates a coordinated network of hormones and neural signals designed to help us respond effectively. Central to this process are corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), adrenaline, cortisol, and other glucocorticoids. Together, these substances form an integrated stress-response system that prepares the body for action, sustains performance during a challenge, and regulates recovery afterward. The Two Arms of the Stress Response The stress response operates through two interconnected systems. The first is the sympathetic nervous system, which produces the immediate "fight-or-flight" response through the release of adrenaline. The second is the hypothalamic-pituitary-adrenal (HPA) axis, which produces a slower but longer-lasting hormonal response involving CRH, ACTH, and...