Noradrenaline (BAN) (abbreviated NA or NAd) or norepinephrine (INN) (abbreviated norepi or NE) is a catecholamine with dual roles as a hormone and a neurotransmitter.[2]
As a stress hormone, norepinephrine affects parts of the brain where attention and responding actions are controlled. Along with epinephrine, norepinephrine also underlies the fight-or-flight response, directly increasing heart rate, triggering the release of glucose from energy stores, and increasing blood flow to skeletal muscle.
However, when norepinephrine acts as a drug it will increase blood pressure by its prominent increasing effects on the vascular tone from α-adrenergic receptor activation. The resulting increase in vascular resistance triggers a compensatory reflex that overcomes its direct stimulatory effects on the heart, called the baroreceptor reflex, which results in a drop in heart rate called reflex bradycardia.
Norepinephrine is synthesized from dopamine by dopamine β-hydroxylase.[3] It is released from the adrenal medulla into the blood as a hormone, and is also a neurotransmitter in the central nervous system and sympathetic nervous system where it is released from noradrenergic neurons. The actions of norepinephrine are carried out via the binding to adrenergic receptors.
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Total Health Breakthroughs
Neurotransmitters in the brain such as norepinephrine are altered by exercise and produce changes similar to those of antidepressants. ...
Zhang, W., Carreno, FR, Cunningham, JT, Mifflin, SW
2009-03-11 07:00:00
We investigated . norepinephrine. (NE) modulation of chemoreceptor afferent integration after a chronic exposure to sustained hypoxia (CSH) (7 8 d at 10% FIO2). Whole-cell recordings of NTS second-order neurons identified by DiA (1 ...
