The naked mole rat is an extraordinary creature that can survive in one of the world's worst environments- arid regions of East Africa. Now, researchers have discovered that the naked mole rat may hold the key to pain relief.

These rats are known to live for 32 years, approximately 200 years for a human, maintain brain activity in low oxygen environment and show resistance to cancer. Medical Daily had previously reported that the researchers are studying these rats to find ways that increase human lifespan.

The naked mole rats live in deep, dark, narrow and long tunnels and their colonies have hundreds of members. The levels of carbon dioxide are so high that air in these tunnels becomes acidic, says Thomas Park, professor of biological sciences at the University of Illinois in Chicago and lead author of the study.

Since a key part of pain is when there is acidification at the injury site, the naked mole rat's survivability in these acidic conditions may offer a possible cure for pain in humans. "Acidification is an unavoidable side-effect of injury. Studying an animal that feels no pain from an acidified environment should lead to new ways of alleviating pain in humans," said Park in a statement.

The mammalian nose is specially equipped with sensory nerve endings that detect the presence of acids in the air and sends messages to an area in the brainstem called the trigeminal nucleus to secrete mucous to protect the nose from the fumes and elicits a behavioral response, like rubbing of the nose, to avoid acidic air. These physiological and behavioral changes keep the animal away from acidic environments.

In the present study, the researchers placed a set of naked mole rats and a set of rats and mice, that acted as controls, in a maze where certain areas had acidic fumes whereas some places were fumes-free. They found that the naked mole rats were as comfortable in the zones with acidic fumes as they were in the fumes-free zone but the control rats kept themselves in the areas that had no acidic fumes. 

Researchers did not find the presence of a protein called c-Fos in the naked mole rats when compared to control rats. This protein is indirectly related to the nerve activity. In the naked mole rats, the researchers found no activity in the trigeminal nucleus whereas control rats and mice showed extensive activity in this region.

The study was published in the journal PLoS ONE