2-Minute Neuroscience: Norepinephrine

Norepinephrine, also known as noradrenaline, is a neurotransmitter and hormone that plays critical roles in the function of the nervous system. In this video, I discuss norepinephrine synthesis, where norepinephrine-producing neurons are concentrated, norepinephrine receptors, and the functions of norepinephrine.

TRANSCRIPT:

Norepinephrine, also known as noradrenaline, is a monoamine neurotransmitter, a term that refers its chemical structure and the fact that it’s derived from an amino acid. It is also a catecholamine, a term that again refers to its chemical structure and the fact that it contains a catechol nucleus. Norepinephrine also functions as a hormone. It is synthesized from dopamine in a reaction catalyzed by the enzyme dopamine beta-hydroxylase.

Norepinephrine-producing neurons in the central nervous system are primarily concentrated in the pons and medulla. The most prominent of these groups of neurons is a nucleus called the locus coeruleus, which is the main site of norepinephrine production for the central nervous system. Norepinephrine is also the primary neurotransmitter used by the sympathetic nervous system, and is found in clusters of sympathetic neurons located near the spinal cord known as sympathetic ganglia. It is also released from the adrenal glands as a hormone.

Norepinephrine acts on g protein-coupled receptors referred to as adrenergic receptors or adrenoceptors. There are thought to be at least three main types of adrenergic receptors, alpha-1, alpha-2 and beta-adrenergic receptors, each of which has multiple subtypes. Norepinephrine is removed from the synaptic cleft by a transport protein called the norepinephrine transporter.

Like any neurotransmitter, the actions of norepinephrine depend on the type of receptor it activates, and where that receptor is located. Thus, although norepinephrine in the central nervous system is frequently associated with arousal, alertness, and attention, the full extent of its actions are more complex. Its release in the sympathetic nervous system is typically associated with responses linked to increased activity, like elevated heart rate and blood pressure.

References:

Bylund DB. Adrenergic Receptors: Historical Perspectives from the 20th Century. In: Perez DM, ed. The Adrenergic Receptors. Totawa, New Jersey: Humana Press, Inc.

Szabadi E. Functional neuroanatomy of the central noradrenergic system. J Psychopharmacol. 2013 Aug;27(8):659-93. doi: 10.1177/0269881113490326.

Tank AW, Lee Wong D. Peripheral and central effects of circulating catecholamines. Compr Physiol. 2015 Jan;5(1):1-15. doi: 10.1002/cphy.c140007.

Wehrwein EA, Orer HS, Barman SM. Overview of the Anatomy, Physiology, and Pharmacology of the Autonomic Nervous System. Compr Physiol. 2016 Jun 13;6(3):1239-78. doi: 10.1002/cphy.c150037.

[NotACupcake]

For people who don’t get the video: Norepinephrine is a hormone. The part of the brain called the “Locus Coeruleus” has the most concentrated amount of this hormone. The body absorbs norepinephrine using adrenergic receptors (a type of cell). Depending on where the norepinephrine ends in the brain it can make you feel aroused and ready to start your day or it can make you want to wrestle an alligator.

[yi]

I've said it before but I'll say it again, really helps when experts like you break it down for us commoners. Cheers

[dmtdreamz]

On a certain level, we have a drug store in our brain, the neurochemicals that show up in flow: so dopamine, norepinephrine, anandamide, endorphins, and serotonin. If you were to try to cocktail the street drug version of that, right, you're trying to blend like heroin and speed and coke and acid and weed- and point is, you can't do it. It turns out the brain can cocktail all of 'em at once, which is why people will prefer flow to almost any experience on Earth. It's our favorite experience. It's the most addictive experience on Earth. Why? 'Cause it cocktails five or six of the largest pleasure drugs the brain can produce. We're all capable of so much more than we know. That is a commonality across the board. And one of the big reasons is we're all hardwired for flow, and flow is a massive amplification of what's possible for ourselves.

[kylebaker]

If you haven't already, you should make a video on corticotropin releasing factor. It plays a major role in lots of stress related illnesses.

[mohittomar]

i am in my 10th grade and this helped me thanks a lot

[unasalus]

This might seem exaggerated, but not really, seen the amount of information out there: I love you

[larrymartinez]

Hello I’ve been having hot flashes for about 3weeks now I’m in good health good libido but I have lost 15 pounds, also work out n eat decent should I worry?

[Twodaythreads]

Thanks Jasper. I cant for the life of me find something like this that explains EPI-nephrine. Why is epi so ignored when discussing pathway origins and projections, starting from brain to cell? Do you have a video on this or do you know who does?

[Ellipsis]

What am I supposed to learn first before I understand this?!? I'm taking atomoxetine and would like to actually understand what the heck its doing.

1:26 Is a perfect screenshot example

[JAdrew]

What is the difference between the prefrontal lobe and yhe cingulate gyrus by function?

[AnnaMaria-dgjv]

So, is the norepenephrine used in postganglionic neurons of the sympathetic system the same one produced in the locus coeruleus? If yes, how does it get there?

[Rimsha]

Okay but SNRI store serotonin and norepinephrine as they are re uptake inhibitors. Serotonin is good for anxiety but why SNRI store epinephrine? Don't they increase brain fight flight mode.

[ILLRICARDO]

would someone with hardcore adhd have noepinephrine dysregulation?

[imanderdumme]

What is that protein? Minutes 2 minus 30 sec

[DarkAngel-cjsx]

Can we increase norepinephrine in the brain?
My son had onset autism and it turned out he has c diff that has attacked his neurotransmitters and his brain can't get the dopamine to be transformed into neropinepherine .
You can imagine the abnormal behaviors that this has caused plus hyperactivity and he has also stopped talking.
His gut is messed up with clostridia ( HPHPA and cresol ) and other overgrowth bacteria.
This has caused abnormal mitochondria as well

[iHeartCoolStuff]

Sorry if this is a dumb question, but when we talk about norepinephrine being responsible for arousal, are we referring to sexual arousal or just general wakefulness?

[jayton]

So does SNRI increase norepinephrine? And is that a good for social anxiety?

[antoinest-cyr]

Nice thanks for this, ( you should try a de-esser next time you edit your videos :) :)

[Diamondlight]

question, so in some textbooks ive heard that norepinephrine is produced in the adrenal glands on top if kidneys, how does this correlate or relate to this system?

[aamirrazak]

Nice vid I’ve never heard of locus ceroulleus before, what’s it’s function