Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Imaging study may help point toward more effective smoking cessation treatments

10.08.2006
Results of a new imaging study, supported in part by the National Institute on Drug Abuse (NIDA), National Institutes of Health, show that the nicotine received in just a few puffs of a cigarette can exert a force powerful enough to drive an individual to continue smoking.

Researchers found that the amount of nicotine contained in just one puff of a cigarette can occupy about 30 percent of the brain's most common type of nicotine receptors, while three puffs of a cigarette can occupy about 70 percent of these receptors. When nearly all of the receptors are occupied (as a result of smoking at least 2 and one-half cigarettes), the smoker becomes satiated, or satisfied, for a time. Soon, however, this level of satiation wears off, driving the smoker to continue smoking throughout the day to satisfy cigarette cravings.

"Imaging studies such as this can add immensely to our understanding of addiction and drug abuse," says Elias A. Zerhouni, M.D., Director of the National Institutes of Health. "These findings suggest that drug therapies or vaccines for smoking cessation need to be extremely potent to compete with nicotine, which binds so readily to these receptors."

The study is published in the August 2006 issue of the Archives of General Psychiatry.

"This study illustrates the powerfully addictive impact of even small amounts of nicotine. Every time a smoker draws a puff from a cigarette, they inhale numerous toxic chemicals that promote the formation of lung cancer, and contribute in a significant way to death and disability worldwide," says NIDA Director Dr. Nora D. Volkow. "Although many smokers endorse a desire to quit, very few are able to do so on their own, and fewer than half are able to quit long-term even with comprehensive treatment. This study helps explain why."

The scientists, led by Dr. Arthur Brody of the David Geffen School of Medicine at UCLA, used positron emission tomography (PET) to scan the brains of 11 smokers and assess nicotine distribution there. During the scanning sessions, the participants smoked one of five amounts--none, one puff, three puffs, one full cigarette, or until their craving was satisfied (2 and one-half to three cigarettes). Craving was measured with the Urge to Smoke scale, which assesses responses to 10 craving-related questions. The scientists also conducted magnetic resonance imaging (MRI) to help localize regions on the PET scans.

"We saw on our PET scans that the radiotracer 'disappeared' over time as the nicotine receptors became occupied by nicotine from cigarettes," says Dr. Brody.

The scientists found that the highest levels of nicotine binding occurred in the thalamus (a portion of the brain that acts as a conduit for all sensory information that reaches the brain's cerebral cortex, and which contains the highest concentration of these nicotine receptors), the brainstem (which controls various automatic functions, such as respiration, heart rate, and arousal), and the cerebellum (the portion of the brain responsible for the coordination of movement and balance). Results of another recently published NIDA-supported study suggest that a portion of the cerebellum called the vermis may be a key factor in modulating the brain's dopamine and reward systems, and may be more involved in drug abuse and addiction than previously thought.

"Although craving was only reduced with near total occupancy of these receptors, there remains the question of whether other, less common types of nicotine receptors are equally important in tobacco dependence," says Dr. Brody. "This is an important area of focus for future research."

"The central findings of the study suggest that typical daily smokers need to have these nicotine receptors almost completely saturated throughout the day, which drives the almost uncontrollable urge to keep smoking," says Dr. Volkow. "A more complete understanding of how nicotine affects the brain can help us develop better therapies for people looking to quit. In addition, since even low levels of nicotine exposure result in substantial occupancy of these receptors, additional research needs to address the impact of secondhand, or environmental, tobacco smoke on nicotine craving."

Sara Rosario Wilson | EurekAlert!
Further information:
http://www.drugabuse.gov
http://www.nida.nih.gov

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>