Navigation Links
Morphine makes lasting -- and surprising -- change in the brain

Morphine, as little as a single dose, blocks the brain’s ability to strengthen connections at inhibitory synapses, according to new Brown University research published in Nature.

The findings, uncovered in the laboratory of Brown scientist Julie Kauer, may help explain the origins of addiction in the brain. The research also supports a provocative new theory of addiction as a disease of learning and memory.

"We’ve added a new piece to the puzzle of how addictive drugs affect the brain," Kauer said. "We’ve shown here that morphine makes lasting changes in the brain by blocking a mechanism that’s believed to be the key to memory making. So these findings reinforce the notion that addiction is a form of pathological learning."

Kauer, a professor in the Department of Molecular Pharmacology, Physiology and Biotechnology at Brown, is interested in how the brain stores information. Long-term potentiation, or LTP, is critical to this process.

In LTP, connections between neurons ?called synapses, the major site of information exchange in the brain ?become stronger after repeated stimulation. This increased synaptic strength is believed to be the cellular basis for memory.

In her experiments, Kauer found that LTP is blocked in the brains of rats given as little as a single dose of morphine. The drug’s impact was powerful: LTP continued to be blocked 24 hours later ?long after the drug was out of the animal’s system.

"The persistence of the effect was stunning," Kauer said. "This is your brain on drugs."

Kauer recorded the phenomenon in the ventral tegmental area, or VTA, a small section of the midbrain that is involved in the reward system that reinforces survival-boosting behaviors such as eating and sex ?a reward system linked to addiction. The affected synapses, Kauer found, were those between inhibitory neurons and dopamine neurons. In a healthy brain, inhibitory cells would limit the release of dopamine, the "pleasure chemical" that gets released by naturally rewarding experiences. Drugs of abuse, from alcohol to cocaine, also increase dopamine release.

So the net effect of morphine and other opioids, Kauer found, is that they boost the brain’s reward response. "It’s as if a brake were removed and dopamine cells start firing," she explained. "That activity, combined with other brain changes caused by the drugs, could increase vulnerability to addiction. The brain may, in fact, be learning to crave drugs."

Kauer and her team not only recorded cellular changes caused by morphine but also molecular ones. In fact, the researchers pinpointed the very molecule that morphine disables ?guanylate cyclase. This enzyme, or inhibitory neurons themselves, would be effective targets for drugs that prevent or treat addiction.
'"/>

Source:Brown University


Related biology news :

1. Morphine for Chest Pain Increases Death Risk
2. University of Manchester makes made-to-measure skin and bones a reality using inkjet printers
3. Grass makes environmentally friendly biofuel
4. Shampoo detergent added to paint makes surfaces self-sterilizing
5. Biota makes major antiviral discovery
6. Green diesel: New process makes liquid transportation fuel from plants
7. Discovery that bacterium is phosphate gourmet key clue to what makes it most social of bacteria
8. Technique makes it easier to see mouse embryo in all its glory
9. In the minds eye: How the brain makes a whole out of parts
10. African parasite makes component of fat differently from all other organisms
11. Coffee makes us more likely to say yes

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:5/23/2017)... -- Hunova, the first robotic gym for the rehabilitation and functional motor sense ... Genoa, Italy . The first 30 robots will be available ... USA . The technology was developed and patented at the IIT ... Movendo Technology thanks to a 10 million euro investment from entrepreneur Sergio ... ...
(Date:4/24/2017)... , April 24, 2017 Janice ... partner with  Identity Strategy Partners, LLP (IdSP) , ... or without President Trump,s March 6, 2017 ... Entry , refugee vetting can be instilled with greater ... (Right now, all refugee applications are suspended by ...
(Date:4/13/2017)... , April 13, 2017 UBM,s Advanced ... will feature emerging and evolving technology through ... Innovation Summits will run alongside the expo portion of ... sessions, panels and demonstrations focused on trending topics within ... advanced design and manufacturing event will take place June ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... ... October 10, 2017 , ... ... pharmaceutical company advancing targeted antibody-drug conjugate (ADC) therapeutics, today confirmed licensing rights ... (Hybrid Polymerized Liposomal Nanoparticle), a technology developed in collaboration with Children’s Hospital ...
(Date:10/10/2017)... International research firm Parks Associates announced today that Tom ... 2017 Annual Meeting , October 11 in Scottsdale, Arizona ... and how smart safety and security products impact the competitive landscape. ... Parks Associates: Smart Home Devices: Main Purchase Driver ... "The residential security market has experienced continued growth, and ...
(Date:10/10/2017)... ... October 10, 2017 , ... The Pittcon Program ... honoring scientists who have made outstanding contributions to analytical chemistry and ... 2018, the world’s leading conference and exposition for laboratory science, which will be ...
(Date:10/9/2017)... , ... October 09, 2017 , ... At its national ... Christopher Stubbs, a professor in Harvard University’s Departments of Physics and Astronomy, has been ... a member of the winning team for the 2015 Breakthrough Prize in Fundamental physics ...
Breaking Biology Technology: