what is norepinephrine

Norepinephrine, also known as noradrenaline, is a chemical that acts as both a neurotransmitter and a hormone. As a neurotransmitter, it helps transmit nerve signals across nerve endings to another nerve cell, muscle cell, or gland cell. As a hormone, it is released by the adrenal glands, which are hat-shaped glands that sit on top of each kidney. Norepinephrine is part of the bodys emergency response system to danger, known as the "fight-or-flight" response. It is involved in increasing alertness, arousal, and attention, constricting blood vessels, and maintaining blood pressure in times of stress. Norepinephrine also plays a role in the sleep-wake cycle, increasing attention and focusing on performing a task, and in memory storage. It is important for emotions, and problems with norepinephrine levels are associated with depression, anxiety, post-traumatic stress disorder, and substance abuse. Norepinephrine can be used to treat septic shock, neurogenic shock, pericardial tamponade, and other conditions.