Stopping cold: Scientists turn off the ability to feel cold

by Robert Perkins

(Medical Xpress)—USC neuroscientists have isolated chills at a cellular level, identifying the sensory network of neurons in the skin that relays the sensation of cold.

David McKemy, associate professor of in the USC Dornsife College of Letters, Arts and Sciences, and his team managed to selectively shut off the ability to sense cold in mice while still leaving them able to sense heat and touch.

In prior work, McKemy discovered a link between the experience of cold and a protein known as TRPM8 (pronounced trip-em-ate), which a sensor of in in the skin, as well as a receptor for menthol, the cooling component of mint. Now, in a paper appearing in the on February 13, McKemy and his co-investigators have isolated and ablated the neurons that express TRPM8, giving them the ability to test the function of these cells specifically.

Using mouse-tracking software program developed by one of McKemy's students, the researchers tested control mice and mice without TRPM8 neurons on a multi-temperature surface. The surface temperature ranged from 0 degrees to 50 degrees Celsius (32 to 122 degrees Farenheit), and mice were allowed to move freely among the regions.

The researchers found that mice depleted of TRPM8 neurons could not feel cold, but still responded to heat. Control mice tended to stick to an area around 30 degrees Celsius (86 degrees Fahrenheit) and avoided both colder and hotter areas. But mice without TRPM8 neurons avoided only hotter plates and not cold—even when the cold should have been painful or was potentially dangerous.

In tests of grip strength, responses to touch, or coordinated movements, such as balancing onto a rod while it rotated, there was no difference between the control mice and the mice without TRPM8-expressing neurons.

By better understanding the specific ways in which we feel sensations, scientists hope to one day develop better pain treatments without knocking out all ability to feel for suffering patients.

"The problem with pain drugs now is that they typically just reduce inflammation, which is just one potential cause of pain, or they knock out all sensation, which often is not desirable," McKemy said. "One of our goals is to pave the way for medications that address the pain directly, in a way that does not leave patients completely numb."

Related Stories

Cold feeling traced to source

Dec 18, 2007

For the first time, neuroscientists have visualized cold fibers – strands reaching from sensory neurons near the spinal cord to nerve endings in the skin tuned to sense different types of cold. The study and pictures appear ...

When do newborns first feel cold?

Jun 17, 2010

Cold sensing neural circuits in newborn mice take around two weeks to become fully active, according to a new study.

The sensation of cold is shut down by inflammation

Jul 02, 2012

(Medical Xpress) -- Research groups at the University of Cambridge and the Instituto de Neurociencias, in Spain, have discovered a new and unexpected mechanism by which cold sensation is regulated, and opens ...

Researchers discover way to block body's response to cold

Mar 01, 2012

Researchers at St. Joseph's Hospital and Medical Center in Phoenix, Arizona, in collaboration with Amgen Inc. and several academic institutions, have discovered a way to block the body's response to cold using a drug. This ...

Recommended for you

Student seeks to improve pneumonia vaccines

22 hours ago

Almost a million Americans fall ill with pneumonia each year. Nearly half of these cases require hospitalization, and 5-7 percent are fatal. Current vaccines provide protection against some strains of the ...

Seabed solution for cold sores

Aug 20, 2014

The blue blood of abalone, a seabed delicacy could be used to combat common cold sores and related herpes virus following breakthrough research at the University of Sydney.

Better living through mitochondrial derived vesicles

Aug 19, 2014

(Medical Xpress)—As principal transformers of bacteria, organelles, synapses, and cells, vesicles might be said to be the stuff of life. One need look no further than the rapid rise to prominence of The ...

Zebrafish help to unravel Alzheimer's disease

Aug 19, 2014

New fundamental knowledge about the regulation of stem cells in the nerve tissue of zebrafish embryos results in surprising insights into neurodegenerative disease processes in the human brain. A new study by scientists at ...

User comments

Adjust slider to filter visible comments by rank

Display comments: newest first

MrVibrating
not rated yet Feb 14, 2013
Weird, i hadn't even considered that a sense of cold existed..!

So is this just a conscious sense then, or are the knockout mice also deprived of subconscious vasoconstriction-type effects?