Known as adrenaline. A member of the catecholamine class of neurotransmitters. Epinephrine is formed from tyrosine, via the two other neurotransmitters dopamine and norepinephrine. Acts as a hormone in its ability to stimulate the breakdown of glycogen stored in skeletal muscle and, to a lesser degree, the liver.
Epinephrine binds to the extracelluar portion of a plasma membrane receptor, the result of which is an increase in intracellular levels of cyclic AMP.