DL-Norepinephrine-d 3 (hydrochloride) is the deuterium labeled DL-Norepinephrine hydrochloride. DL-Norepinephrine hydrochloride is a synthetic phenylethylamine that mimics the sympathomimetic actions of the endogenous norepinephrine.DL-Norepinephrine hydrochloride is a neurotransmitter targets α1 and β1 adrenoceptors, has an increasing effect on subendocardial oxygen tension.