I’ve always liked the way these two words conjure up mental images. Epinephrine brings to mind the Epi Pen, a potentially lifesaving device for people who deal with certain types of allergies. Adrenaline brings to mind the Road Runner of cartoon fame, cruising along at break neck speed.
Those images help explain epinephrine’s function, both as a hormone and neurotransmitter, to get the body revved up in response to a perceived threat or excitement. This response is known as “fight or flight” because adrenaline is released when the body perceives an event to which it needs to respond by “fight or flight”.
While not all excitement is negative, the body prepares itself just in case. Adrenaline is released in the adrenal glands (located above the kidneys and not in the brain) in reaction to a message begun in the amygdala. The amygdala does not waste time figuring out if something is a threat or not; instead it responds rapidly with the aim of protecting you if necessary. The signal goes from the amygdala to the hypothalamus to the pituitary gland (all of which are located in the brain) and then to the adrenal glands located mid-body. The adrenal glands then release adrenaline.Thus, your hands might get clammy before making a presentation or performing, and you might wish you could be invisible, but hopefully you are simply excited and not overly threatened, and you manage to go on with the show!
[9/23/08 – For a delightful look at adrenaline, please skoot on over to this post on 1000 Awesome Things: #934 Adrenaline. I came upon this post thanks to the blog cross-referencing feature of WordPress.]