Navigation Links
Researchers reveal why some pain drugs become less effective over time

MONTREAL, April 3, 2012 Researchers at the University of Montreal's Sainte-Justine Hospital have identified how neural cells like those in our bodies are able to build up resistance to opioid pain drugs within hours. Humans have known about the usefulness of opioids, which are often harvested from poppy plants, for centuries, but we have very little insight into how they lose their effectiveness in the hours, days and weeks following the first dose. "Our study revealed cellular and molecular mechanisms within our bodies that enables us to develop resistance to this medication, or what scientists call drug tolerance," lead author Dr. Graciela Pineyro explained. "A better understanding of these mechanisms will enable us to design drugs that avoid tolerance and produce longer therapeutic responses."

The research team looked at how drug molecules would interact with molecules called "receptors" that exist in every cell in our body. Receptors, as the name would suggest, receive "signals" from the chemicals that they come into contact with, and the signals then cause the various cells to react in different ways. They sit on the cell wall, and wait for corresponding chemicals known as receptor ligands to interact with them. "Until now, scientists have believed that ligands acted as 'on- off' switches for these receptors, all of them producing the same kind of effect with variations in the magnitude of the response they elicit," Pineyro explained. "We now know that drugs that activate the same receptor do not always produce the same kind of effects in the body, as receptors do not always recognize drugs in the same way. Receptors will configure different drugs into specific signals that will have different effects on the body."

Pineyro is attempting to tease the "painkilling" function of opioids from the part that triggers mechanisms that enable tolerance to build up. "My laboratory and my work are mostly structured around rational drug design, and trying to define how drugs produce their desired and non desired effects, so as to avoid the second, Pineyro said. "If we can understand the chemical mechanisms by which drugs produce therapeutic and undesired side effects, we will be able to design better drugs."

Once activated by a drug, receptors move from the surface of the cell to its interior, and once they have completed this 'journey', they can either be destroyed or return to the surface and used again through a process known as "receptor recycling." By comparing two types of opioids DPDPE and SNC-80 the researchers found that the ligands that encouraged recycling produced less analgesic tolerance than those that didn't. "We propose that the development of opioid ligands that favour recycling could be away of producing longer-acting opioid analgesics," Pineyro said.


Contact: William Raillant-Clark
University of Montreal

Related biology technology :

1. Researchers Identify New Regulator in Allergic Diseases
2. CNIO researchers take part in the most comprehensive personalized medicine study performed to date
3. Researchers develop graphene supercapacitor holding promise for portable electronics
4. Researchers capture first-ever images of atoms moving in a molecule
5. Penn researchers build first physical metatronic circuit
6. Pitt researchers coax gold into nanowires
7. York researchers create tornados inside electron microscopes
8. Self-assembling nanorods: Berkeley Lab researchers obtain 1-, 2- and 3-D nanorod arrays and networks
9. Navy researchers investigate small-scale autonomous planetary explorers
10. Notre Dame researchers develop paint-on solar cells
11. Quantum computing has applications in magnetic imaging, say Pitt researchers
Post Your Comments:
(Date:11/25/2015)... ... November 25, 2015 , ... Jessica Richman and ... early in their initial angel funding process. Now, they are paying it forward ... make early stage investments in the microbiome space. In this, they join ...
(Date:11/24/2015)... ... November 24, 2015 , ... The United States Golf Association (USGA) today ... Green Section Award. Presented annually since 1961, the USGA Green Section Award recognizes an ... turfgrass. , Clarke, of Iselin, N.J., is an extension specialist of turfgrass ...
(Date:11/24/2015)... , Nov. 24, 2015 Halozyme Therapeutics, Inc. (NASDAQ: ... Conference in New York on Wednesday, December ... Helen Torley , president and CEO, will provide a corporate overview. ... New York at 1:00 p.m. ET/10:00 a.m. PT . ... investor relations, will provide a corporate overview. --> th ...
(Date:11/24/2015)... , ... November 24, 2015 , ... ... healthy metabolism. But unless it is bound to proteins, copper is also toxic ... (NIH), researchers at Worcester Polytechnic Institute (WPI) will conduct a systematic study of ...
Breaking Biology Technology:
(Date:10/29/2015)... Oct. 29, 2015  Connected health pioneer, Joseph ... explosion of technology-enabled health and wellness, and the business ... The Internet of Healthy Things . ... smartphones even existed, Dr. Kvedar, vice president, Connected Health, ... care delivery, moving care from the hospital or doctor,s ...
(Date:10/27/2015)... , Oct. 27, 2015 Synaptics Inc. (NASDAQ: ... announced that Google has adopted the Synaptics ® ... solutions to power its newest flagship smartphones, the Nexus ... --> --> ... to provide strategic collaboration in the joint development of ...
(Date:10/23/2015)... GOLETA, California , October 23, 2015 ... and SensoMotoric Instruments (SMI) announce a mobile plug and ... captured during interactive real-world tasks SensoMotoric Instruments ... of their established wearable solutions for eye tracking and ... behavior captured with SMI Eye Tracking Glasses 2w ...
Breaking Biology News(10 mins):