Navigation Links
Research sheds new light on heroin addiction
Date:5/14/2008

Researchers from the Howard Florey Institute in Melbourne have identified a factor that may contribute towards the development of heroin addiction by manipulating the adenosine A2A receptor, which plays a major role in the brains reward pathway.

Using mice specifically bred without the adenosine A2A receptor, Prof Andrew Lawrence and his team showed that these mice had a reduced desire to self-administer morphine; heroin is converted to morphine in the body. The mice also self-administered less morphine compared to control littermates, but did not develop tolerance to specific behavioural effects of morphine.

The researchers also found that the mice did not develop a conditioned place preference for the drug, indicating that drug-context associations are mediated in part by this receptor. In human terms, this equates to the associative memory of the environment where the drug is used.

Collectively, these findings strongly suggest that the adenosine A2A receptor is involved in regulating the reinforcing and motivational properties of opiates.

Prof Lawrence said this was the first study to show that the adenosine A2A receptor was implicated in self-motivation to take opiates such as heroin.

This receptor clearly plays a major role in opiate use and therefore abuse, as the mice were simply not interested in taking morphine despite it being freely available, he said.

Although the drug-taking effects and behaviours of these mice were diminished, they still relapsed into drug-seeking after a period of withdrawal.

This indicates that the adenosine A2A receptor has a role in the getting high aspects of addiction, but not in the adaptations that contribute to relapse after going cold turkey.

The results from this study reinforce that addiction is a highly complex brain disorder that will require a multi-pronged approach to treat.

Australia has over 50,000 heroin users. There are effective medical treatments available, such as methadone, buprenorphine and suboxone, as well as psychological interventions, but a better understanding of how heroin affects the brain could lead to improvements and broadening of these treatment options.

Drugs alone will not be the answer successful treatment of drug addiction will require a combination of drugs and psychotherapy, Prof Lawrence said.

Drugs alone will not be the answer successful treatment of drug addiction will require a combination of drugs and attention to social and psychological factors, Prof Lawrence said.

A number of major pharmaceutical companies are developing drugs that block the adenosine A2A receptor, so Prof Lawrences research provides even more evidence that this receptor is an important target for treating drug addiction.

Prof Lawrence said that drugs affecting the adenosine A2A receptor show preclinical promise to treat alcohol addiction.

Earlier this year we found that the adenosine A2A receptor interacts with the mGlu5 glutamate receptor found in the brains reward pathway to regulate drug-seeking. Consequently, a drug developed to target both these receptors could have an even better result in treating addiction, he added.


'/>"/>

Contact: Merrin Rafferty
merrin.rafferty@florey.edu.au
61-383-441-658
Research Australia
Source:Eurekalert

Related medicine news :

1. Stanford researchers find culprit in aging muscles that heal poorly
2. Children of depressed moms do better when dad is involved, SLU researcher finds
3. UCLA researchers identify markers that may predict diabetes in still-healthy people
4. Mayo Clinic researchers discover new diagnostic test for detecting infection in prosthetic joints
5. New research shows how chronic stress worsens neurodegenerative disease course
6. New research explores newborn in-hospital weight loss
7. Research may unlock mystery of autisms origin in the brain
8. Bipolar disorder relapses halved by Melbourne researchers
9. HIVs impact in Zimbabwe explored in new research
10. U.S. Research Funding Continues to Flatten as U.S. Health Costs Climb - in August 31 Science
11. Cell that triggers symptoms in allergy attacks can also limit damage, Stanford researchers find
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/20/2017)... ... 2017 , ... Yisrayl Hawkins, Pastor and Overseer at The House of Yahweh has posted a ... Yisrayl says this generation is a time like no other and society needs to understand ... Yisrayl says he does not want to sound like an old bible beater because religion ...
(Date:1/20/2017)... , ... January 20, 2017 , ... Bionic Sports Nutrition ... walks of life, announced it had a successful January ECRM Trade Show in Hilton ... the United States, which allows it to provide its products to all clients at ...
(Date:1/20/2017)... ... 2017 , ... International Protein, a company based out of Australia that focuses ... January ECRM trade show in Hilton Head, SC. , International Protein was founded ... a line of products that would elevate her fitness regime. At this ECRM trade ...
(Date:1/20/2017)... ... January 20, 2017 , ... Vitamin Well has launched ... The drinks have been produced in collaboration with Zlatan Ibrahimovic and have been ... , After a successful launch in Sweden last year, the next generation sports ...
(Date:1/20/2017)... ... ... account following a man who went on to support his country and serve the Lord. ... Haven, Florida and at the age of 5, his family moved to Pensacola Florida. In ... and got married right out of boot camp. , He and his wife raised ...
Breaking Medicine News(10 mins):
(Date:1/19/2017)... , Jan. 19, 2017 ViewRay, Inc. ... a federal institution supporting research in Germany ... and patient treatments at the University Clinic Heidelberg as ... The MRIdian Linac program will be headed by ... also heads radiation oncology at the German Cancer Research ...
(Date:1/19/2017)... 19, 2017   Science Exchange , the leading ... that the first five replication studies from the ... published in eLife today. Despite intense scrutiny around ... practical evaluation of reproducibility rates that may identify ... other assessments of reproducibility, the results of this ...
(Date:1/19/2017)... , January 19, 2017 ... Option to Address Motor Symptoms and Motor Complications ... ...      (Logo: http://photos.prnewswire.com/prnh/20151014/276718LOGO) ... , European Neurological Review,2016;11(Suppl. 2): 2-15, http://www.touchneurology.com/articles/safinamide-new-therapeutic-option-address-motor-symptoms-and-motor-complications-mid-late ...
Breaking Medicine Technology: