(Image source: Wikimedia Commons)

BY STEVEN SPARKMAN

ANCHOR CHRISTINA HARTMAN

They’re some of the ugliest critters you can lay eyes on, and also some of the most interesting for scientists to study. Now, the naked mole rat might carry the key to treating chronic pain.

African naked mole rats, named for... well, obvious reasons, live in underground tunnel networks. Not only do they look weird, when compared to other mammals -- especially rodents -- they’re absolutely bizarre. A writer for io9 lists a few of their traits. (Video source: Cornell University)

“The glabrous little buggers live decades longer than most other rodents, never develop cancer, and have mastered the enviable skill of being able to run backwards as quickly as they do forwards. They are also, as it turns out, completely impervious to the excruciating pain of an acid burn -- and now researchers think they know why.”

Naked mole rats live in colonies with a social structure resembling an insect hive. They pack themselves so tightly into their tunnels that the CO2 they exhale reaches painfully toxic levels -- but the stoic rodents never seem to notice.

ABC Australia reports researchers first examined the rats’ nerves cells in the lab to see whether they were immune to acid.

“This type of pain response is carried in nerves called C fibres, which give rise to the aching or burning 'after pain' we feel after sunburn, for instance. Like humans, naked mole rats have C fibres and they also have the receptors at the end of these nerves that can detect acid. When the team tested the acid receptors on mole rat nerve cells (neurons) they were amazed to find they worked perfectly normally.”

So if their nerves reacted, why weren’t the rats feeling any pain from the acid? A writer for Science 2.0 explains, researchers were looking at the wrong part of the cell.

“...the researchers shifted their focus to another type of channel … When comparing the channels’ response to acid, the authors found that, in mice, the pain signal dropped 42%, and in naked mole rats 63%. According to the researchers, this means that the pain signal reaches the brain in mice, but not in naked mole rats.”

If you didn’t catch that, basically the rats’ nerve cells were reacting to the presence of acid, but that same acid blocked the cell from sending signals to the rest of the nervous system. It’s like shouting into a severed phone line -- the signal goes in, but never gets passed along.

New Scientist spoke to a researcher who laid out what this research could mean for humans.

“...this sodium channel could be a target for the development of drugs to prevent the pain caused by acid build-up – which happens in arthritis and other inflammatory disorders. ‘You could potentially develop a drug to bind to that site and reduce its activity to make people less sensitive to pain.’”

It turns out naked mole rats also don’t react to the chemical in hot peppers, but this new research doesn’t explain why. So they may have even more pain-related secrets to uncover.