A hormone that is released by the medulla of the adrenal gland and acts on the alpha and beta adrenergic receptors. Adrenaline, also known as epinephrine (especially in the Unitd States), makes the heart beat faster. It also makes the bronchi open and diverts blood from the skin and digestive system to the heart and muscles. Adrenaline plays a central role in the short-term stress reaction – the physiological response to threatening or exciting conditions (fight-or-flight response). Synthetic adrenaline is used medicinally in some situations, especially in the resuscitation of patients in shock or following cardiac arrest.
