Navigation Links
Receptor variant influences dopamine response to alcohol
Date:5/18/2010

A genetic variant of a receptor in the brain's reward circuitry plays an important role in determining whether the neurotransmitter dopamine is released in the brain following alcohol intake, according to a study led by researchers at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health. Dopamine is involved in transmitting the euphoria and other positive subjective effects produced by alcohol.

A report of the findings, which help explain the diverse genetic susceptibility for alcohol use disorders, will appear online in Molecular Psychiatry on May 18, 2010.

"By advancing our understanding of the neurobiology that underlies the addictive properties of alcohol, this finding helps us understand why alcohol affects people in very different ways," says NIAAA Acting Director Kenneth R. Warren, Ph.D. "This kind of information also aids the development of personalized medications for alcohol problems."

Receptors for brain molecules known as opioid peptides help initiate the neurochemical reactions that underlie the positive effects produced by alcohol. Activation of the mu-subtype of opioid receptor following alcohol consumption triggers the release of dopamine from the forebrain.

"But there is much variation in alcohol-induced responses that are thought to be related to dopamine," explains Markus Heilig, M.D., Ph.D., NIAAA clinical director and the study's senior author. "Previous studies by our group and others suggest that variants of opioid genes may contribute to the observed variation, possibly through effects on alcohol-induced dopamine release."

He notes, for example, that people who carry the mu-opioid receptor variant designated as 118G report increased euphoria following alcohol consumption. Dr. Heilig's group has reported that a similar mu-opioid receptor variant in monkeys heightened the stimulating effects of alcohol and increased their alcohol consumption.

In the current study, first author Vijay A. Ramchandani, Ph.D., an investigator in NIAAA's Laboratory of Clinical and Translational Studies, Dr. Heilig, and their colleagues explored whether the 118G mu-opioid receptor variant influences dopamine release from a forebrain region called the ventral striatum in response to alcohol.

Using human positron emission tomography (PET), an imaging technique that allowed the researchers to analyze dopamine activity in the brain, they compared dopamine release in two groups of people that had been given a dose of alcohol. The groups consisted of those who carried a copy of the gene for the 118G mu-opioid receptor variant, and those who carried only genes for the more common 118A variant. They found that only people with the 118G variant had a dopamine response to alcohol no such response happened in subjects with the 118A receptor variant.

In a separate experiment, they inserted genes for the human 118G or 118A mu-opioid receptor variants into mice and then directly measured the animals' dopamine response to a dose of alcohol. Mice with the 118G variant showed a fourfold higher peak dopamine response to the alcohol challenge compared to mice with the 118A variant.

"Taken together, our data strongly support a causal role of the 118G variant of the mu-opioid receptor to confer a more vigorous dopamine response to alcohol in the ventral striatum," says Dr. Ramchandani. "The findings add further support to the notion that individuals who possess this receptor variant may experience enhanced pleasurable effects from alcohol that could increase their risk for developing alcohol abuse and dependence. It may also explain why these individuals, once addicted, benefit more from treatment with blockers of endogenous opioids."


'/>"/>

Contact: John Bowersox
niaaapressoffice@mail.nih.gov
301-443-3860
NIH/National Institute on Alcohol Abuse and Alcoholism
Source:Eurekalert

Related biology news :

1. Gene-based stem cell therapy specifically removes cell receptor that attracts HIV
2. Stress peptide and receptor may have role in diabetes
3. Developmental delay could stem from nicotinic receptor deletion
4. Common herbicides and fibrates block nutrient-sensing receptor found in gut and pancreas
5. Caltech scientists get detailed glimpse of chemoreceptor architecture in bacterial cells
6. Endothelin receptor may play role in sickle cell pain
7. Study reveals a reprogrammed role for the androgen receptor
8. Grant supports LSUHSC research on how like cell receptor systems determine very different functions
9. Flexible neck in cell-receptor DC-SIGN targets more pathogens
10. Scientists explain how death receptors designed to kill our cells may make them stronger
11. Newly discovered epidermal growth factor receptor active in human pancreatic cancers
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... FRANCISCO and BANGALORE, India , ... of EdgeVerve Systems, a product subsidiary of Infosys (NYSE: ... provider, today announced a global partnership that will ... way to use mobile banking and payment services. ... is a key innovation area for financial services, but it ...
(Date:4/15/2016)... , April 15, 2016  A new partnership ... more accurate underwriting decisions in a fraction of ... competitively priced and high-value life insurance policies to ... With Force Diagnostics, rapid testing (A1C, ... data readings (blood pressure, weight, pulse, BMI, and ...
(Date:3/31/2016)... PROVIDENCE, R.I. , March 31, 2016  Genomics ... leadership of founding CEO, Barrett Bready , M.D., ... addition, members of the original technical leadership team, including ... Vice President of Product Development, Steve Nurnberg and Vice ... have returned to the company. Dr. Bready ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... the release of its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” ... and retention in this eBook by providing practical tips, tools, and strategies for ...
(Date:6/23/2016)... , June 23, 2016 Houston Methodist ... the Cy-Fair Sports Association to serve as their ... agreement, Houston Methodist Willowbrook will provide sponsorship support, ... connectivity with association coaches, volunteers, athletes and families. ... the Cy-Fair Sports Association and to bring Houston ...
(Date:6/23/2016)... ... June 23, 2016 , ... Supplyframe, the ... the Supplyframe Design Lab . Located in Pasadena, Calif., the Design Lab’s ... how hardware projects are designed, built and brought to market. , The Design ...
(Date:6/23/2016)... LONDON , June 23, 2016 ... & Hematology Review, 2016;12(1):22-8 http://doi.org/10.17925/OHR.2016.12.01.22 ... Review , the peer-reviewed journal from touchONCOLOGY, ... the escalating cost of cancer care is placing ... a result of expensive biologic therapies. With the ...
Breaking Biology Technology: