How Do Pain Relievers Work? - George Zaidan

Translator: Ido Dekkers Reviewer: Ariana Bleau Lugo

Translator: Daniel Lopez Reviewer: Servizo de Normalización Lingüística

Say you're at the beach, and you get sand in your eyes.

Estás na praia e éntrache area nos ollos.

How do you know the sand is there?

Como sabes que tes area neles?

You obviously can't see it, but if you are a normal, healthy human,

Obviamente non podes vela, pero se es unha persoa sa normal,

podes sentila,

you can feel it,

that sensation of extreme discomfort, also known as pain.

esa sensación de incomodidade extrema, tamén chamada dor.

Now, pain makes you do something,

Entón, a dor impúlsate a facer algo,

in this case, rinse your eyes until the sand is gone.

neste caso, lavar os ollos ata que a area se vaia.

And how do you know the sand is gone?

E como sabes que xa non está?

Exactly. Because there's no more pain.

Exacto: porque xa non hai dor.

There are people who don't feel pain.

Hai persoas que non senten dor.

Now, that might sound cool, but it's not.

Iso pode soar ben, pero non o está.

If you can't feel pain, you could get hurt, or even hurt yourself

Se non sentes dor, podes mancarte, incluso a ti mesmo,

and never know it.

e nunca te darías conta.

Pain is your body's early warning system.

A dor é un sistema de aviso rápido.

It protects you from the world around you, and from yourself.

Protexe o teu corpo do entorno que o rodea e de ti mesmo.

A medida que medramos, instálanse detectores da dor por todo o corpo.

As we grow, we install pain detectors in most areas of our body.

These detectors are specialized nerve cells

Estes son células nerviosas especializadas chamados nociceptores

called nociceptors

that stretch from your spinal cord to your skin, your muscles, your joints,

que se estenden desde a medula espiñal ata a pel, os músculos, as articulacións,

your teeth and some of your internal organs.

os dentes e algúns órganos internos.

Just like all nerve cells, they conduct electrical signals,

Igual que as neuronas, conducen sinais eléctricos

sending information from wherever they're located back to your brain.

e envían información desde a súa localización ata o cerebro.

But, unlike other nerve cells,

Porén, a diferenza doutras neuronas,

nociceptors only fire if something happens that could cause

os nociceptores só se activan se algo causa ou está causando un dano.

or is causing damage.

So, gently touch the tip of a needle.

Se tocas con coidado a punta dunha agulla,

sentirás o metal. Esas son as células nerviosas normais.

You'll feel the metal, and those are your regular nerve cells.

Pero non sentirás dor.

But you won't feel any pain.

Now, the harder you push against the needle,

Se premes con forza contra a agulla,

the closer you get to the nociceptor threshold.

acercaraste ao limiar da dor.

Push hard enough, and you'll cross that threshold

Premendo coa forza suficiente, pasarás o límite e activaranse os nociceptores,

and the nociceptors fire,

telling your body to stop doing whatever you're doing.

que avisan o corpo de que pare o que está a facer.

But the pain threshold isn't set in stone.

Pero este límite non é fixo.

Algúns compostos poden afectar aos nociceptores

Certain chemicals can tune nociceptors, lowering their threshold for pain.

e baixar o limiar da dor.

When cells are damaged, they and other nearby cells

Cando se danan as células, estas, xunto con outras próximas,

start producing these tuning chemicals like crazy,

comezan a liberar estes compostos coma tolas

e a baixar o limiar dos nociceptores

lowering the nociceptors' threshold to the point

ata o punto en que o mero contacto produce dor.

where just touch can cause pain.

And this is where over-the-counter painkillers come in.

E aquí é onde entran en xogo os analxésicos comúns.

Aspirin and ibuprofen

A aspirina e o ibuprofeno

block production of one class of these tuning chemicals,

bloquean a produción dun destes compostos,

called prostaglandins.

chamados prostaglandinas.

Botemos unha ollada a como o fan.

Let's take a look at how they do that.

When cells are damaged, they release a chemical called arachidonic acid.

Cando hai un dano celular, libérase un composto chamado ácido araquidónico.

Dous enzimas denominados COX-1 e COX-2

And two enzymes called COX-1 and COX-2

convert this arachidonic acid into prostaglandin H2,

converten este ácido araquidónico en prostaglandina H2,

which is then converted into a bunch of other chemicals

que se pode transformar nunha chea de compostos con diferentes accións,

that do a bunch of things,

including raise your body temperature, cause inflammation

como aumentar a temperatura corporal,

causar unha inflamación e baixar o limiar da dor.

and lower the pain threshold.

Todos os enzimas teñen un sitio activo.

Now, all enzymes have an active site.

That's the place in the enzyme where the reaction happens.

Este é o lugar do enzima onde ten lugar a reacción.

The active sites of COX-1 and COX-2

Os sitios activos de COX-1 e COX-2

axústanse ao ácido araquidónico á perfección.

fit arachidonic acid very cozily.

As you can see, there is no room to spare.

Como se pode ver, non sobra sitio.

E é neste sitio onde a aspirina e o ibuprofeno fan o seu traballo,

Now, it's in this active site that aspirin and ibuprofen do their work.

So, they work differently.

pero de diferente forma.

A aspirina actúa como unha espiña dun ourizo.

Aspirin acts like a spine from a porcupine.

It enters the active site and then breaks off,

Entra no sitio activo, rompe

leaving half of itself in there,

e deixa unha parte dentro,

totally blocking that channel and making it impossible

que bloquea o sitio e fai imposible que encaixe o ácido araquidónico.

for the arachidonic acid to fit.

This permanently deactivates COX-1 and COX-2.

Isto desactiva de forma permanente COX-1 e COX-2.

Por outra banda, o ibuprofeno entra no sitio activo,

Ibuprofen, on the other hand,

enters the active site,

but doesn't break apart or change the enzyme.

pero non rompe nin cambia o enzima.

COX-1 and COX-2 are free to spit it out again,

COX-1 e COX-2 son capaces de librarse del,

but for the time that that ibuprofen is in there,

pero, mentres o ibuprofeno estea unido,

the enzyme can't bind arachidonic acid, and can't do its normal chemistry.

o ácido araquidónico non se une ao enzima, polo que non funciona de forma normal.

Pero como saben a aspirina e o ibuprofeno onde se localiza a dor?

But how do aspirin and ibuprofen know where the pain is?

Well, they don't.

Ben, non o saben.

Unha vez os medicamentos chegan ao sangue,

Once the drugs are in your bloodstream,

they are carried throughout your body,

transpórtanse por todo o corpo,

and they go to painful areas just the same as normal ones.

e acaban chegando ás zonas doridas igual que ao resto.

Esta é a forma en que funcionan a aspirina e o ibuprofeno.

So that's how aspirin and ibuprofen work.

But there are other dimensions to pain.

Pero hai outras dimensións de dor.

Neuropathic pain, for example,

A dor neuropática, por exemplo,

is pain caused by damage to our nervous system itself;

débese a un dano no propio sistema nervioso;

there doesn't need to be any sort of outside stimulus.

non necesita ningún estímulo externo

And scientists are discovering that the brain controls

e os científicos están descubrindo que o cerebro controla como respondemos á dor.

how we respond to pain signals.

Por exemplo, a cantidade de dor que sentes depende de se lle estás a prestar atención

For example, how much pain you feel can depend on

whether you're paying attention to the pain, or even your mood.

ou incluso do teu estado de ánimo.

Pain is an area of active research.

A dor é unha grande área de estudo.

If we can understand it better, maybe we can help people manage it better.

Se a entendemos mellor, quizais poidamos axudar as persoas a levala mellor.