Norepinephrine (NE) is both a neurotransmitter and a hormone. Also called noradrenaline, NE plays a key role in the “fight or flight” response by spiking your heart rate and blood pressure. NE is similar to adrenaline and many experts believe it helps determine your basic levels of stimulation and arousal. NE also is linked to anxiety and depression. High NE levels are associated with feelings of joy, and sometimes euphoria.
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