Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Chili peppers continue to help unravel mechanism of pain sensation

26.02.2009
Capsaicin, the active ingredient in chili peppers, generally is viewed as an irritant that produces a burning sensation when applied to a sensitive area of the body, such as the cornea.

Paradoxically, the same compound also may reduce pain. Capsaicin creams are natural pain-relieving folk medicines, commonly found over the counter, and are effective for a variety of pain syndromes, from minor muscle or joint aches to those that are very difficult to treat, such as arthritis and neuropathic pain.

Scientists at University at Buffalo now link the analgesic effects of capsaicin to a lipid called PIP2 in the cell membranes.

Results of the research, headed by Feng Qin, Ph.D., associate professor in the Department of Physiology and Biophysics in the University at Buffalo's School of Medicine and Biomedical Sciences, appear Feb. 24 in the journal PLoS Biology.

Capsaicin works by stimulating a receptor on nerve endings in the skin, which sends a message to the brain and generates the sensation of pain. The receptor also senses heat, making chili peppers taste hot.

"The receptor acts like a gate to the neurons," said Qin. "When stimulated it opens, letting outside calcium enter the cells until the receptor shuts down, a process called desensitization. The analgesic action of capsaicin is believed to involve this desensitization process. However, how the entry of calcium leads to the loss of sensitivity of the neurons was not clear."

Previous research from the UB group and others implicated the significance of the PIP2 lipid. Calcium influx induces strong depletion of the lipid in the plasma membrane. By combining electrical and optical measurements, the authors now have been able to directly link the depletion of PIP2 to the desensitization of the receptor.

The authors also found that the receptor is still fully functional after desensitization. "What changed was the responsiveness threshold," said Qin. "In other words, the receptor had not desensitized per se, but its responsiveness range was shifted. This property, called adaptation, would allow the receptor to continuously respond to varying stimuli over a large capsaicin concentration range."

"Adaptation" is a property that is found in other sensory receptors, such as those in hearing and vision, and is identified in pain receptors as well.

The findings have implications for pain-sensation mechanisms as well as clinical applications, the authors note. With an adaptive response, the receptors are essentially autoregulated without a fixed threshold. The intensity that causes pain is dependent on the history of activity.

Plasticity of pain is known at the central level. The study now shows that it may also be present at the peripheral site, although the sensation of pain is complex and involves many types of receptors and messengers. The lipid dependence of the receptor also will provide novel strategies for development of safe analgesics like capsaicin, a natural pain reliever, but with less irritation.

Jing Yao, Ph.D., a post-doctoral research student in the UB Department of Physiology and Biophysics, is second author on the paper.

The study was supported by a grant from the National Institutes of Health.

The University at Buffalo is a premier research-intensive public university, a flagship institution in the State University of New York system and its largest and most comprehensive campus. The School of Medicine and Biomedical Sciences is one of five schools that constitute UB's Academic Health Center. UB's more than 28,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities.

Lois Baker | EurekAlert!
Further information:
http://www.buffalo.edu

More articles from Health and Medicine:

nachricht Speed data for the brain’s navigation system
06.12.2016 | Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE)

nachricht Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

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:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

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...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

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...

Im Focus: Quantum Particles Form Droplets

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...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

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,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>