The blind, furless creatures that live underground in colonies lack a body chemical called Substance P, a neurotransmitter normally in the skin that sends pain signals to the central nervous system. The rats feel no immediate pain when cut, scraped or subjected to heat stimuli. They only feel some aches. But when the rats get a shot of Substance P, pain signaling resumes working as in other mammals.
"It was a complete surprise when we discovered that the skin of naked mole-rats is missing one of the most basic chemicals that's found in the skin of all other mammals," said Thomas Park, associate professor of biological sciences at the University of Illinois at Chicago and the principal investigator in the research project.
Co-investigators include Christopher Comer, professor of biological sciences, Ying Lu, assistant professor of anesthesiology and Charles Laurito, professor of anesthesiology -- all at UIC -- along with pharmacologists Frank Rice of the Albany Medical College in Albany, N.Y. and Steven Wilson, of the University of South Carolina School of Medicine.
The findings were reported in a presentation by Lu Nov.8 in New Orleans at the annual meeting of the Society for Neuroscience.
Some medical researchers believe an excess of Substance P causes the human condition fibromyalgia, where patients suffer from chronic pain in soft fibrous body tissue such as muscles, ligaments and tendons. Theoretically, reducing or eliminating Substance P in affected areas could ease the pain. Experiments using naked mole-rats may help test this hypothesis and perhaps lead to new therapies.
"After we discovered that naked mole-rats naturally lacked Substance P, we realized that we had a unique situation whereby we could try to re-introduce
Contact: Paul Francuch
University of Illinois at Chicago