or noradrenaline
One of two catecholamine hormone s ( epinephrine is the other) secreted by the adrenal gland s, as well as at nerve endings, as a neurotransmitter .
It resembles adrenaline chemically and in its actions on the body, which mimic sympathetic nervous system stimulation. It constricts most blood vessels and is given for certain types of shock . Norepinephrine is formed from tyrosine and converted to epinephrine. It was discovered by Ulf von Euler-Chelpin (1905–83) in the mid-1940s.