2-Minute Neuroscience: Opioids

In this video, I discuss a few of the ways opioid drugs affect the brain, as well as the basis for opioid tolerance and withdrawal.

TRANSCRIPT:

Welcome to 2 minute neuroscience, where I explain neuroscience topics in 2 minutes or less. In this installment I will discuss opioids.

The term “opioid” refers to substances that bind to opioid receptors, usually to exert pain-relieving effects. Opioids can be found naturally in the opium poppy, or they can be partially or completely synthetic. In addition to pain relief, opioids also cause sedation, anxiety reduction, and euphoria, along with a variety of other effects.

When opioids bind to opioid receptors, they promote potassium conductance, which makes a neuron less likely to fire an action potential, and they inhibit calcium conductance, which makes a neuron less likely to release neurotransmitters. What effect these actions have depends on where the receptors are found. When opioid receptors on neurons in the spinal cord that carry information about pain are activated, it can inhibit the transmission of pain information to the brain.

Opioids can also act on descending pain modulatory systems to reduce pain. For example, by binding to receptors an area of the brainstem called the periaqeuductal gray, opioids can prompt the inhibition of pain signaling in the spinal cord via a pathway that first synapses in the medulla.

Opioids can reduce the emotional impact of pain by acting in brain regions like the anterior cingulate cortex, and they increase dopamine levels in areas like the nucleus accumbens, which may contribute to the reinforcing qualities of the drugs.

Exposure to opioid drugs leads to tolerance, which involves a decreased response to the drug and a need to take more to produce the same effect. The mechanisms of opioid tolerance aren’t fully understood, but they’re thought to involve adaptive changes like a reduction in the number of functional receptors for the drug to act at. Adaptations in response to the presence of the drug also lead to dysregulation when the drug is removed, and withdrawal effects that are opposite in many ways to the typical effects of the drug.

References:

Bailey CP1, Connor M. Opioids: cellular mechanisms of tolerance and physical dependence. Curr Opin Pharmacol. 2005 Feb;5(1):60-8.

Corder G, Castro DC, Bruchas MR, Scherrer G. Endogenous and Exogenous Opioids in Pain. Annu Rev Neurosci. 2018 Jul 8;41:453-473. doi: 10.1146/annurev-neuro-080317-061522. Epub 2018 May 31.

[the.kai.eros.experience]

I was just hit by a car a few days ago and got prescribed hydrocodone.

It’s a feeling I’ve never experienced.

So chill and euphoric.

It’s scary good.

It’s not like MDMA where you can feel almost overstimulated and too excited.

It’s peaceful.

I heard someone say it felt like being hugged by Jesus.

Yes, lol.

I have a deeper understanding of people who become addicted now.

Especially if everything is a mess in life why wouldn’t you chase a peaceful feeling?

It’s fascinating that we are walking chemistry sets.

[iKazed]

I always like neat science stuff on opioids that isn't innately loaded with judgment and the typical hysteria. Props!

[bununii]

so glad this channel has so many videos!!! i’m a neuroscience student travelling to san francisco soon and was researching the fentanyl crisis there. it’s so important to understand what’s happening in the body on these drugs!!

[playc.holder]

One of my favorite channels!!!! Can’t focus much longer than one of these episodes

[eishaghazanfar]

You have always come up with the concise content required! Thank you!

[carolenekurien]

You are so good at explaining in a concise, engaging manner. One of my favorite channels to use as a study source!!

[julialebrero]

i cant tell you how much you've helped me through uni <3 simple, concise and useful info!! LOVE U

[ChillingCrowley]

Slight correction, Opioids are compounds that bind to opiate receptors but are not derived from the opium poppy - fentanyl or tramadol for examples. Opiates are compounds that are found in opium poppy or are synthesised from the opium poppy such as codeine or oxycodeone. It's a minor detail but should be mentioned

[XWorgosX]

I love your short clear and concise videos, keep it up <3

[pillowfortwithrooandaimee]

Hello. May I have permission to use this video in an eLearning for doctor's and therapists? We do not charge for our trainings. Thanks.

[PrivelegedPilots]

Anyone else high off a perc right now?

[malamri]

Thank you so much this is very approachable

[emmynordlund]

Does anybody know which pathway the pathway is? The descending one that synapses in the medulla?

[pfeliciano]

Promoting potassium conductance makes the neuron less likely to fire an action potential? If potassium leaves the cell, we reach repolarization and get closer to the relative refractory period, reaching the Vr, which should allow the cell to reach an action potential faster within 1-2ms.

[madophelia]

interesting video. Opioids are fascinating :)

[novicechess]

I have a question. Adverse effects of opioids depend on the responses activated by the receptors.

[BrianCarnevaleB]

"It's not what you do, it's how you do it!"!

Take them sporadically and receive all of the happiness & PAIN RELIEF without any after-effects like DRINKING!

So few can do this, but some can with strong self-discipline.

[mike]

The euphoria they give is out of this world

[mill]

1:22 What do you mean when you say the reinforcing qualities of the drugs?

[GustavoHenrique-wdfn]

Meu Deus abençoe a todos envolvidos no video e familias e todos aqui nos comentarios e familias em nome do Senhor Jesus Cristo🙏🙏🙏🙏🙏🙏🙏777