From the Guidelines
Catecholamine release is primarily triggered by activation of the sympathetic nervous system in response to stress, physical exertion, or perceived threats, as well as certain medical conditions like pheochromocytoma, which can cause excessive catecholamine production, as noted in the 2024 European Heart Journal guidelines 1. This "fight-or-flight" response causes the adrenal glands to secrete epinephrine (adrenaline) and norepinephrine (noradrenaline) into the bloodstream. Specific triggers include:
- Physical stressors like pain, injury, exercise, extreme temperatures, and hypoglycemia (low blood sugar)
- Psychological stressors such as fear, anxiety, and emotional distress
- Certain medications and substances, including caffeine, nicotine, amphetamines, and cocaine Additionally, some medical conditions like pheochromocytoma (a tumor of the adrenal gland) can cause excessive catecholamine production, as discussed in the 2023 Lancet Diabetes and Endocrinology guidelines 1. At the cellular level, this process involves neural signals that trigger calcium influx into adrenal medulla cells, leading to exocytosis of catecholamine-containing vesicles. These catecholamines then produce widespread effects throughout the body, including increased heart rate, blood pressure, respiratory rate, and blood glucose levels to prepare the body for action. It is also important to note that hereditary pheochromocytoma/paraganglioma syndromes, such as those associated with SDHB-related tumors, can result in significant clinical morbidity related to mass effect, cranial nerve palsies, or hypertension/tachycardia resulting from catecholamine excess, as highlighted in the 2017 Clinical Cancer Research study 1.
From the Research
Catecholamine Release Causes
- Physical challenges, emotional arousal, increased physical activity, or changes in the environment can evoke stress, requiring altered activity of visceral organs, glands, and smooth muscles, leading to catecholamine release 2
- The brain's stress-handling system, including the limbic-hypothalamic-pituitary-adrenal axis, plays a key role in regulating the response to stress and catecholamine release 3
- Various stimuli that cause stress or arousal in the body can lead to increased release of catecholamines, such as noradrenaline and adrenaline 4
- Activation of the sympathetic nervous system is responsible for the body's "fight or flight" reaction, which is mediated through the action of catecholamines on adrenergic receptors 5
Catecholamine-Producing Tumors
- Pheochromocytoma is a catecholamine-producing tumor of the sympathetic nervous system, which can cause excessive catecholamine release and lead to symptoms such as hypertension, sweating, and anxiety attacks 6
Stress-Related Catecholamine Release
- Stress-axis activation can lead to the release of catecholamines, which play a key role in the alterations provoked by stress-axis activation 3
- The rise in circulating epinephrine and norepinephrine from the adrenal medulla and norepinephrine secreted from sympathetic nerve terminals can cause increased blood pressure and cardiac output, relaxation of smooth muscles, and metabolic changes 2