平特五不中

Researchers at 平特五不中 have discovered that a protein found in the membrane of our sensory neurons are involved in our capacity to feel mechanical pain, laying the foundation for the development of powerful new analgesic drugs.

The study, published in , is the first to show that TACAN, a highly conserved protein among vertebrates whose function remained unclear, is in fact involved in detecting mechanical pain by converting mechanical pressures into electric signals.

Using molecular and cellular approaches with electrophysiology, Reza Sharif-Naeini, a professor in 平特五不中鈥檚 Department of Physiology, and his team were able to establish that TACAN is found on the membrane of pain sensing cells where it forms tunnel like pores, a structure known as an ion channel.

The researchers also created a mouse model where TACAN could be 鈥渢urned off,鈥� making the animals significantly less sensitive to painful mechanical stimuli.

鈥淭his demonstrates that TACAN contributes to sensing mechanical pain,鈥� says Sharif-Naeini, who is also the study鈥檚 senior author.

A decade-long search

About 70 years ago, scientists imagined that tiny sensors might be responsible for providing our brain with useful information about our environment, explaining our sense of touch or our capacity to feel pain when pinched.

These sensors have since been discovered to be ion channels - pore like structures capable of translating mechanical pressures exerted on a cell into electrical signals that travel to the brain to be processed - a phenomenon known as mechanotransduction.

This phenomenon has been shown to be central in several physiological processes such as hearing, touch and the sensation of thirst. But the identity of the sensor responsible for mechanical pain remained elusive.

Because 鈥渕ost of the pain we feel - a pinch or a stubbed toe - is mechanical in nature,鈥� Sharif-Naeini said that competition to find the newly discovered sensor was fierce.

With the rampant problem of opioid overuse, the finding has practical implications for people who suffer from chronic pain. Patients with conditions such as osteoarthritis, rheumatoid arthritis or neuropathic pain often develop mechanical allodynia, a condition where mechanical pain receptors become overly sensitive. Trivial things such as walking or a light touch thus become extremely painful, leading to a significant reduction in the quality of their lives.

鈥淣ow that we have identified the sensor associated with mechanical pain, we can start designing new powerful analgesic drugs that can block its action. This discovery is really exciting and brings new hope for novel pain treatment,鈥� adds Sharif-Naeini.

Photo caption: Marine Christin, co-first author on the new study, and Reza Sharif-Naeini

鈥溾�� by Lou Beaulieu-Laroche et al. was published in Cell.

This work was supported by the Canadian Institutes of Health Research and the Groupe d鈥櫭﹖ude des prot茅ines membranaires.