Navigation Links
When do newborns first feel cold?
Date:6/17/2010

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

The finding adds to understanding of the cold sensing protein TRPM8 (pronounced trip-em-ate), first identified in a Nature paper in 2002 by David McKemy of the University of Southern California.

McKemy's latest study, published online by Neuroscience, shows that the cold sensing circuit starts to develop in utero but does not mature until well after birth.

"About three or four days before the animal is born, the protein is expressed. However, the axons of these nerves going into the spinal cord are not fully formed until probably two weeks after birth," McKemy said.

The delay in development of cold sensing is plausible, McKemy added.

"In the womb, when would we ever feel cold?"

By contrast, mice are born with a keen sense of smell, which they need to breast feed successfully.

Direct study of the cold sensing protein TRPM8 in humans is not yet possible. While sensory development differs in mice and humans mice are born blind, for example the study suggests a possible biological basis for findings of altered cold sensitivity in children.

In a 2008 study of temperature sensation by the Institute of Child Health at University College London, researchers found that 11-year-old children born prematurely were less sensitive to temperature than those born at term.

"This is consistent with our observations that the circuitry is not fully developed until after birth, thus anything that disrupts this formation at this important stage could have long term effects," McKemy noted.

"There are other reports that injury and inflammation in rodent models that occur during the (prenatal) period lead to altered temperature sensitivity as well as altered neural circuits."

The USC researchers tracked development of cold sensing through mice genetically engineered to express a green fluorescent protein whenever TRPM8 was produced.

TRPM8 is one in a class of proteins known as ion channels. Their purpose is to "turn on the cell" when they receive a stimulus. TRPM8 senses both painful cold and the soothing cold of menthol-based creams.

How one protein can convey both sensations is unknown. McKemy speculated that neurons differ in their internal architecture, with each tuned to accept either painful or pleasant cold signals from TRPM8.

One goal of TRPM8 research is to understand the molecular mechanisms of sensation, in the hope of developing better drugs for relief of chronic pain states, such as the extreme sensitivity to cold experienced by some diabetes patients.

"If you want to understand conditions like cold allodynia, which is cold pain, you need to find exactly what are the targets," McKemy said.

"If we understand the basic nuts and bolts of the molecules and neurons and how they detect pain normally," McKemy said, "then perhaps we can figure out why we detect pain when we shouldn't."


'/>"/>

Contact: Carl Marziali
marziali@usc.edu
213-740-4751
University of Southern California
Source:Eurekalert

Related biology news :

1. MIT: Prenatal arsenic exposure detected in newborns
2. Crib-side studies help struggling newborns go home without feeding tubes
3. Experimental treatment halts hypoxic-ischemic brain injury in newborns
4. Researchers work on vaccine to improve immune system in newborns
5. Bilingual babies: The roots of bilingualism in newborns
6. Which came first, the moth or the cactus?
7. First all-African GM crop is resistant to maize streak virus
8. Scientists retrace evolution with first atomic structure of an ancient protein
9. CU-Boulder team discovers first ancient manioc fields in Americas
10. First finding of a metabolite in 1 sex only
11. First orchid fossil puts showy blooms at some 80 million years old
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/26/2016)... India and LONDON ... Infosys Finacle, part of EdgeVerve Systems, a product ... and Onegini today announced a partnership to integrate ... solutions.      (Logo: http://photos.prnewswire.com/prnh/20151104/283829LOGO ... to provide their customers enhanced security to access ...
(Date:4/19/2016)... 20, 2016 The new GEZE ... compact web-based "all-in-one" system solution for all door components. ... or the door interface with integration authorization management system, ... systems. The minimal dimensions of the access control and ... building installations offer considerable freedom of design with regard ...
(Date:4/15/2016)... 15, 2016 Research and ... Biometrics Market 2016-2020,"  report to their offering.  , ... , ,The global gait biometrics market is expected ... the period 2016-2020. Gait analysis generates ... be used to compute factors that are not ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... ... innovative medical technologies, services and solutions to the healthcare market. The company's primary ... various distribution, manufacturing, sales and marketing strategies that are necessary to help companies ...
(Date:6/24/2016)... TOKYO , June 24, 2016  Regular discussions on ... to take place between the two entities said Poloz. ... in Ottawa , he pointed to the ... and the federal government. ... Poloz said, "Both institutions have common economic goals, why not ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... the release of its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” ... and retention in this eBook by providing practical tips, tools, and strategies for ...
(Date:6/23/2016)... Md. , June 23, 2016 A person ... from the crime scene to track the criminal down. ... the U.S. Food and Drug Administration (FDA) uses DNA evidence ... Sound far-fetched? It,s not. The FDA ... sequencing to support investigations of foodborne illnesses. Put as simply ...
Breaking Biology Technology: