Generality
The measurement of plasma or urinary metanephrines represents a simple and reliable test for the screening of pheochromocytoma.
Metanephrines derive from the metabolism of catecholamines, hormones produced and secreted by the adrenal medulla in order to prepare the body to deal with stressful events.
What are
- Metanefines and normetanephrine are metabolites of epinephrine (adrenaline) and norepinephrine (noradrenaline).
- Epinephrine and norepinephrine are catecholamines (hormones) that help regulate blood flow and pressure in the body, and play an important role in the stress response.
- Catecholamines are produced by the medulla (inner portion) of the adrenal glands and are secreted into the blood.
- Once these hormones have completed their action, they are metabolized to inactive compounds:
- Norepinephrine is converted to normetanephrine and vanylmandelic acid (VMA);
- Epinephrine is converted to metanephrine and VMA.