A type of neurohormone (a chemical that is made by nerve cells and used to send signals to other cells). Catecholamines are important in stress responses. High levels cause high blood pressure which can lead to headaches, sweating, pounding of the heart, pain in the chest, and anxiety. Examples of catecholamines include dopamine, epinephrine (adrenaline), and norepinephrine (noradrenaline).