what happens to our body when we’re in too much pain? and how opioids (morphine, tramadol) help ?


what happens to our body when we’re in too much pain? and how opioids (morphine, tramadol) help ?

In: Biology

If you’re in immense pain, you can go into something called “pain shock”.

For example if you stuck your hand in lava you probably wouldn’t feel it. (Though this is also because you scorched off your receptors)

Morphine is an opioid receptor agonist

Our body is full of all kinds of receptors, for simplicity, it’s full of little locks which require specific keys to unlock them to activate their effect. I.e. when someone gets an adrenaline shot from an epipen (adrenaline is the key in this instance) it goes and unlocks a whole bunch of locks to which it fits into to cause a number of effects.

e.g. alpha 1 receptors (or alpha 1 locks) when bound (unlocked) by adrenaline cause your blood vessels to contract and increase your blood pressure. But adrenaline will also go bind to a whole bunch of other receptors (locks) like beta 2, to which there is a high amount in the lungs and it causes the vessels in the lungs to dilate – i.e. bronchodilation. That’s why adrenaline is given to treat anaphylactic shock (where your BP drops rapidly and your airways close).

In the case of morphine, it’s a similar mechanism, instead it binds to opioid receptors (there are a whole bunch of these that do different things, but in terms of pain, they bind to 2 specific points to stop the pain, a pre-synaptic vesicle and post synaptic vesicle.

In the pre-synaptic inhibition, essentially what the morphine is doing is stopping your brain sending down messages that the pain is actually happening/causing you pain.

In the post synaptic inhibition morphine is essentially stopping the messages from the brain being received.

If the brain can’t send signals to your body to say it’s in pain or your body can’t receive it (pre and post synaptic inhibition) you don’t get pain.

On my phone but I hope that makes sense.

Edit: [My anki card literally came up for this today so if you’re seeking some more detailed info.](https://imgur.com/a/to5BfxD)