"This discovery has implications for how we perceive hot and cold temperatures and for why people with certain forms of chronic pain, such as neuropathic pain, or pain arising as direct consequence of a nervous system injury or disease, experience heightened responses to cold temperatures," says Zylka, a member of the UNC Neuroscience Center.
The neural circuit that senses heat and itch is labeled in red. Neural circuits that process other sensory stimuli are labeled in blue and green. The image is from the spinal cord.
Credit: Zylka Lab, UNC School of Medicine
The study also has implications for why a promising new class of pain relief drugs known as TRPV1 antagonists (they block a neuron receptor protein) cause many patients to shiver and "feel cold" prior to the onset of hyperthermia, an abnormally elevated body temperature. Enhanced cold followed by hyperthermia is a major side effect that has limited the use of these drugs in patients with chronic pain associated with multiple sclerosis, cancer, and osteoarthritis.
Zylka's research sheds new light on how the neural circuits that regulate temperature sensation bring about these responses, and could suggest ways of reducing such side-effects associated with TRPV1 antagonists and related drugs.
The research was selected by the journal Neuron as cover story for the April 10, 2013 print edition and was available in the April 4, 2013 advanced online edition.
This new study used cutting edge cell ablation technology to delete the nerve circuit that encodes heat and some forms of itch while preserving the circuitry that sense cold temperatures. This manipulation results in animals that were practically "blind" to heat, meaning they could no longer detect hot temperatures, Zylka explains. "Just like removing heat from a room makes us feel cold (such as with an air conditioner), removing the circuit that animals use to sense heat made them hypersensitive to cold. Physiological studies indicated that these distinct circuits regulate one another in the spinal cord."
TRPV1 is a receptor for heat and is found in the primary sensory nerve circuit that Zylka studied. TRPV1 antagonists make patients temporarily blind to heat, which Zylka speculates is analogous to what happened when his lab deleted the animals' circuit that detects heat: cold hypersensitivity.
Zylka emphasizes that future studies will be needed to confirm that TRPV1 antagonists affect cold responses in a manner similar to what his lab found with nerve circuit deletion.
The study was conducted in the Zylka lab by postdoctoral scientists Eric S. McCoy, Sarah E. Street, and Jihong Zheng and by research associates Bonnie Taylor-Blake and Alaine Pribisco. Funding for the research came from the Searle Scholars Program, The Klingenstein Foundation, The Rita Allen Foundation, the National Institute of Neurological Disorders and Stroke (NINDS) and the National Institute of Child Health and Human Development (NICHD).
Les Lang | EurekAlert!
Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT
Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
06.12.2016 | Materials Sciences
06.12.2016 | Medical Engineering
06.12.2016 | Power and Electrical Engineering