NPY works as a natural tranquilizer that controls anxiety and buffers the effects of stress hormones like norepinephrine.
1868, from normal (in reference to molecular structure) + epinephrine.
norepinephrine nor·ep·i·neph·rine (nôr'ěp-ə-něf'rĭn)
n.
A substance, both a hormone and neurotransmitter, secreted by the adrenal medulla and the nerve endings of the sympathetic nervous system to cause vasoconstriction and increases in heart rate, blood pressure, and the sugar level of the blood. Also called levarterenol, noradrenalin.