The Science Behind Salt and Wounds: Osmosis?

AI Thread Summary
The discussion centers on why salt (NaCl) causes increased pain when applied to a wound. Participants suggest that the pain may be linked to osmosis, where the salt creates a hypertonic environment, drawing water out of cells and leading to cellular damage. This cellular damage is interpreted as pain by the nervous system. The role of sodium (Na+) and chloride (Cl-) ions in nerve impulses is also mentioned, with the hypothesis that their interaction with nerve cells could trigger pain signals. Additionally, the comparison to slugs highlights that larger organisms have protective skin layers that prevent salt from causing harm, whereas a wound compromises this barrier, allowing salt to affect the underlying tissues. Overall, the conversation combines elements of biology, chemistry, and physiology to explore the mechanisms behind the pain caused by salt in wounds.
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Why does the wound hurt more if you pour salt (NaCl) on it? Does it have something to do with osmosis?
 
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Guess - the NaCl would dissociate and the ions would cause the pain.

Unless of course you were a slug and then you hypertonic solution would suck all of the fluid out of your body and you would die.

Nautica
 
but how? does Na+ or cl- ions react with nerves better than other substances or what
 
Too much of Na+ is not good. It will cause a hypertonic solution which will damgage the cell.

But Like I said I am not sure if this is what causes the pain, it was just a guess.

Nautica
 
I kinda agree with the slug idea - the reason you don't die if you touch salt, is that you are bigger than a slug, and you have an impermeable layer - the skin. With a wound, you lose the layer, and so in bodily fluids can make water leave your cells by osmosis. The damage would probably register as pain.
 
The Na+ and Cl-, if it somehow is absorbed into a nerve cell at different rates, would cause electrical imbalances which could push it over the threashold and cause them to fire - hence pain.

Half guessing.. half braining.
 
I'm going to agree with Jikx.

K+ and Na+ ions are both involved in nerve impulses. To begin a nerve impulse, the stimuli triggers a release of Na+ ions into the axon, which causes a chain reaction of Na+ being pumped in all through the nerve. Pain is a construct of our brains to interpret some nerve impulses. I'm guessing that this particular nerve impulse is the same as pain.

Though, like Jikx, I'm pretty much making an educated guess.
 
Wow! Is there a competition to see who can resurrect the oldest thread? ;-)
 
If you put salt on a necropost, will it hurt?
 
  • #10
Yes. Mentors.
 
  • #11
turbo-1 said:
Wow! Is there a competition to see who can resurrect the oldest thread? ;-)

I cannot see dates on PF mobile.
Anyways it's not that hard considering you always have the link to the last page on the thread list.
 
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  • #12
I just happened to Google: "Why does salt in a wound cause pain" or something to that extent.
 
  • #13
I agree with Jikx, but there may be more to it than a nerve firing, as sodium would indeed upset the osmotic pressure in cells, which they wouldn't like one bit. I think this may be why even choanoflagellates seem to have sodium channels (or at least the genes for them), even though said single cell animals obviously don'y have their own neurons!:
http://www.physorg.com/news/2011-05-sodium-channels-evolved-animals-nervous.html"
 
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