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Which hormones are involved in the fight-or-flight response?
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The fight-or-flight response is a complex physiological reaction to acute threats, coordinated by the autonomic nervous system and the endocrine system. Several key hormones are involved in mediating this process:1
- Catecholamines (Epinephrine and Norepinephrine): Secreted by the adrenal medulla, these hormones are central to the immediate response. They increase heart rate, elevate blood pressure, and stimulate the breakdown of liver glycogen into glucose to provide rapid energy.12
- Cortisol: Released by the adrenal cortex, cortisol helps the body manage stress by further increasing blood glucose levels and supporting cardiovascular function.13
- Glucagon: Secreted by the pancreas, this hormone works in concert with others to raise blood sugar levels, ensuring the body has sufficient fuel for the physical demands of the response.1
These hormones collectively prepare the body to react or retreat by enhancing alertness, increasing cardiac output, and mobilizing energy reserves.12