PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

TSRI study shows how exercise could reduce relapse during meth withdrawal

TSRI study shows how exercise could reduce relapse during meth withdrawal
2014-11-04
(Press-News.org) LA JOLLA, CA – November 3, 2014 – Scientists at The Scripps Research Institute (TSRI) have found that even brief workouts can reduce the risk of relapse in rats withdrawing from methamphetamine. In addition, the team found that exercise affected the neurons in a brain region that had never before been associated with meth withdrawal, suggesting a new direction for drug development.

"There was no correlation between length of workout and risk of relapse—it's the mere involvement in the activity of physical fitness, rather than how much time you can put in," said TSRI Associate Professor Chitra Mandyam, senior author of the new study, published in the journal Brain Structure and Function. "That's really important if we are going to translate this to humans."

These research results come as the number of methamphetamine users rises in the United States, according to the U.S. Department of Health and Human Service's 2013 National Survey on Drug Use and Health. In San Diego County, this rise has had dire consequences, with the county reporting a 55-percent increase in meth-related deaths since 2008.

"Right now, there is no FDA-approved medicine for methamphetamine addiction," Mandyam noted. "Discovering novel pathways in the brain that could be associated specifically with the withdrawal and relapse stage may lead to new avenues for therapeutics."

The Impact of Exercise

In a 2013 study, Mandyam and her colleagues had shown that running during methamphetamine use reduced the amount of methamphetamine that rats chose to consume. By investigating the brain chemistry involved, the team found that both running and drug use activated the brain's reward system—apparently rats that exercised didn't need as much methamphetamine to be satisfied.

For the current study, the researchers wanted to see whether running could play a similar protective role in methamphetamine withdrawal.

To find out, they set up an experiment using two groups of rats. One group had access to running wheels during withdrawal; the other did not. During the addiction stage, the rats were allowed to choose how much methamphetamine to consume. During the withdrawal stage, they could also choose how often to run on a wheel.

"Right off the bat, we noticed that the rats going through withdrawal did get on the running wheels when given access to them, but they didn't run as much as drug-naïve rats," said Mandyam.

The rats given access to running wheels, however, showed a reduction in drug-seeking behavior, meaning that they were less likely to press a lever to request a dose of methamphetamine after the drug had been withdrawn. This finding echoes observations of decreased drug-seeking in cocaine and nicotine-addicted rats given access to running wheels during withdrawal.

How the Brain Changes

The researchers went on to determine the brain region associated with this difference in behavior.

They measured neurotoxicity and the activity of neurons in the brain, and were surprised to find that running reduced the number of dopamine neurons in the periaqueductal grey (PAG), an area of the brain associated with pain-sensing. Scientists had long known that opiates, such as heroin, affected the PAG, but a change had never been seen during the withdrawal stage from a stimulant such as methamphetamine.

The researchers suggest that the connection between the dopamine neurons in the PAG and neurons in a region of the brain called the central nucleus of the amygdala, which is associated with negative reinforcement, could be driving relapse behavior in methamphetamine-addicted animals.

Mandyam said that more experiments are needed to determine exactly how the PAG and central nucleus of the amygdala interact. Mandyam is also studying whether changes in the PAG occur in rats withdrawing from alcohol and is interested in whether any significant differences can be found in the brain structure.

INFORMATION:

In addition to Mandyam, other contributors to the study, "Chronic wheel running-induced reduction of extinction and reinstatement of methamphetamine seeking in methamphetamine dependent rats is associated with reduced number of periaqueductal gray neurons," are Jeffrey C. Sobieraj, Airee Kim and McKenzie J. Fannon, all of TSRI.

Support for this study came from the National Institute on Drug Abuse (DA022473 and DA034140), National Institute on Alcoholism and Alcohol Abuse (AA020098 and AA06420) and Alcohol Beverage Medical Research Foundation. For more information on this study, see http://link.springer.com/article/10.1007%2Fs00429-014-0905-7


[Attachments] See images for this press release:
TSRI study shows how exercise could reduce relapse during meth withdrawal

ELSE PRESS RELEASES FROM THIS DATE:

Lactose intolerants at lower risk of certain cancers: Study

2014-11-04
People with lactose intolerance are at lower risk of suffering from lung, breast and ovarian cancers, according to a new study by researchers at Lund University and Region Skåne in Sweden. "We found that people with lactose intolerance, who typically consume low amounts of milk and other dairy products, have a reduced risk of lung, breast and ovarian cancers", says Jianguang Ji, Associate Professor at Lund University and researcher at the Center for Primary Care Research in Malmö. "The risk of cancer was not reduced in relatives of people with lactose intolerance, ...

Nature adores a hybrid

Nature adores a hybrid
2014-11-04
This news release is available in French. Montreal, November 4, 2014 — Overfishing, climate change and pollution have reduced fish populations in Canadian lakes and rivers. While hatchery-raised fish could return numbers to normal, they aren't as well adapted to their new environments, and there's been concern that the wild population is "tainted" once it breeds with its domesticated counterparts. But new research from Concordia, published in the journal Evolutionary Applications, shows that after a few generations of breeding and natural selection, these ...

Hot flushes are going unrecognised leaving women vulnerable

2014-11-04
Hot flushes are one of the most distressing conditions faced by women who have been treated for breast cancer, but they are not being adequately addressed by healthcare professionals and some women consider giving up their post cancer medication to try and stop them, a new study has shown. More than 70 per cent of women who have had breast cancer experience menopausal problems, and hot flushes in particular, which are among the most prevalent and potentially distressing problems following breast cancer treatment. These can also be long lasting, persisting for more than ...

Hermit thrush or humans: Who sets the tone?

Hermit thrush or humans: Who sets the tone?
2014-11-04
This news release is available in German. Many musical cultures around the world use pitch systems in which notes are related by simple integer proportions (ratios between note frequencies) corresponding to the harmonic (overtone) series. The diatonic major scale, prevalent in Western music, is a typical example. For a long time, scientists have debated the relative contribution of biology and culture in shaping these pitch systems. One way to answer this question is to study animal "song": if the vocal displays of some animals, such as birds or whales, follow some ...

Improving the taste of alcohol-free beer with aromas from the regular beer

Improving the taste of alcohol-free beer with aromas from the regular beer
2014-11-04
Consumers often complain that alcohol-free beer is tasteless, but some of the aromas it is lacking can be carried across from regular beer. Researchers from the University of Valladolid (Spain) have developed the technique and a panel of tasters has confirmed its effectiveness. The alcohol in beer acts as a solvent for a variety of aromatic compounds; therefore, when it is eliminated, as in non-alcoholic beers, the final product loses aromas and some of its taste. It is difficult to recover these compounds, but researchers from the University of Valladolid have done just ...

Autism spectrum disorder: Ten tips guidance article

2014-11-04
Washington D.C., November 4, 2014 – A Clinical Perspectives article published in the November 2014 issue of the Journal of the American Academy of Child and Adolescent Psychiatry proposes a tool to empower stakeholders, guide caregivers, and provide a rationale for advocates, when considering the systems of support offered to people with an autism spectrum disorder (ASD). Organizations such as the American Academy of Child and Adolescent Psychiatry, the European Society for Child and Adolescent Psychiatry, the International Association for Child and Adolescent Psychiatry ...

Asthma patients reduce symptoms and improve lung function with shallow breaths, more CO2

Asthma patients reduce symptoms and improve lung function with shallow breaths, more CO2
2014-11-04
Asthma patients taught to habitually resist the urge to take deep breaths when experiencing symptoms were rewarded with fewer symptoms and healthier lung function, according to a new study from Southern Methodist University, Dallas. The findings are from a large clinical trial funded with a grant from the National Institutes of Health. The results suggest asthma patients using behavioral therapy in conjunction with their daily asthma medicine can improve their lung health over the long-term, said principal investigators Thomas Ritz and Alicia E. Meuret, both SMU clinical ...

Half of elderly people are more than happy to consume new foods

2014-11-04
This news release is available in Spanish. Elderly people are regarded as traditional consumers, but the AZTI study reveals that there are more and more elderly people who are happy to accept new foods. However, these consumers insist that the new proposals should be similar to or evoke traditional products and flavours and, at the same time, be health-enhancing, have the right nutrient profile for their age, and be flavoursome. To come up with new foods adapted to the needs of the population over 65, AZTI –in collaboration with the ADIMEN group of sociologists ...

New technique may help assess how plastic pollution impacts wildlife

2014-11-04
By swabbing oil from a gland located at the end of a seabird's tail and analyzing the sample with gas chromatography-mass spectrometry, researchers have developed a way to measure wildlife's exposure to plastics. The minimally invasive technique will prove useful for detecting plastics exposure at population and species levels. Such monitoring is increasingly important as annual plastics production continues to rise—production has increased from less than 2 tons per year in the 1950s to nearly 280 million tons in 2011. "We're excited about this new method we've ...

Populations of common birds across europe are declining

2014-11-04
Across Europe, the population of common birds has declined rapidly over the last 30 years, while some of the less abundant species are stable or increasing in number. The findings, which come from a 30-year data set of 144 bird species, are worrisome because the most common species of birds provide most of the benefits for humans, for example by controlling agricultural pest species, dispersing seeds, and simply providing beautiful birdsongs. "It is becoming increasingly clear that interaction with the natural world and wildlife is central to human wellbeing, and significant ...

LAST 30 PRESS RELEASES:

Are lifetimes of big appliances really shrinking?

Pink skies

Monkeys are world’s best yodellers - new research

Key differences between visual- and memory-led Alzheimer’s discovered

% weight loss targets in obesity management – is this the wrong objective?

An app can change how you see yourself at work

NYC speed cameras take six months to change driver behavior, effects vary by neighborhood, new study reveals

New research shows that propaganda is on the rise in China

Even the richest Americans face shorter lifespans than their European counterparts, study finds

Novel genes linked to rare childhood diarrhea

New computer model reveals how Bronze Age Scandinavians could have crossed the sea

Novel point-of-care technology delivers accurate HIV results in minutes

Researchers reveal key brain differences to explain why Ritalin helps improve focus in some more than others

Study finds nearly five-fold increase in hospitalizations for common cause of stroke

Study reveals how alcohol abuse damages cognition

Medicinal cannabis is linked to long-term benefits in health-related quality of life

Microplastics detected in cat placentas and fetuses during early pregnancy

Ancient amphibians as big as alligators died in mass mortality event in Triassic Wyoming

Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly

Alcohol makes male flies sexy

TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income

Study links teen girls’ screen time to sleep disruptions and depression

Scientists unveil starfish-inspired wearable tech for heart monitoring

Footprints reveal prehistoric Scottish lagoons were stomping grounds for giant Jurassic dinosaurs

AI effectively predicts dementia risk in American Indian/Alaska Native elders

First guideline on newborn screening for cystic fibrosis calls for changes in practice to improve outcomes

Existing international law can help secure peace and security in outer space, study shows

Pinning down the process of West Nile virus transmission

UTA-backed research tackles health challenges across ages

In pancreatic cancer, a race against time

[Press-News.org] TSRI study shows how exercise could reduce relapse during meth withdrawal