A new study in “Biological Psychiatry” reports that smoking-related deficits in brain dopamine, a chemical implicated in reward and addiction, return to normal three months after quitting. The normalization of dopamine systems suggests smoking-related deficits are a consequence of chronic smoking, rather than a risk factor. These findings raise the possibility that treatments might be developed that normalize the dopamine system in smokers.
According to first author Dr. Lena Rademacher, Postdoctoral fellow at the University of Lübeck, Germany, a major challenge in understanding substance-related disorders lies in uncovering why only some individuals become addicted.
Researchers think some people could possess a trait that predisposes them to addiction, and suspect that brain circuits involving dopamine may be involved. Drugs of abuse release dopamine, and addiction to nicotine is associated with abnormalities in the dopamine system. But researchers are uncertain if smoking induces those abnormalities or if they already exist and contribute to risk of nicotine addiction.
Senior author Dr. Ingo Vernaleken, Professor at RWTH Aachen University, Germany led a team of researchers examining dopamine function in chronic smokers before and after long-term cessation.
The researchers used a brain imaging technique called positron emission tomography to measure an index of the capacity for dopamine production in 30 men who were nicotine-dependent smokers and 15 nonsmokers. After performing an initial scan on all participants, 15 smokers who successfully quit were scanned again after three months of abstinence from smoking and nicotine replacement.
The initial scan revealed a 15–20% reduction in the capacity for dopamine production in smokers compared with nonsmokers. The researchers expected this impairment to persist even after quitting, which would suggest it could be a marker of vulnerability for nicotine addiction.
“Surprisingly, the alterations in dopamine synthesis capacity normalized through abstinence,” said Rademacher.
The role of dopamine in vulnerability toward nicotine addiction cannot be excluded, but the findings suggest that altered dopamine function of smokers is a consequence of nico-tine consumption rather than the cause.
Dr. John Krystal, Editor of “Biological Psychiatry”, noted the implications of these findings for developing better ways to help smokers trying to quit. “This study suggests that the first three months after one stops smoking may be a particularly vulnerable time for relapse, in part, because of persisting dopamine deficits. This observation raises the possibility that one might target these deficits with new treatments.”
The article is "Effects of Smoking Cessation on Presynaptic Dopamine Function of Addicted Male Smokers" by Lena Rademacher, Susanne Prinz, Oliver Winz, Karsten Hen-kel, Claudia A. Dietrich, Jörn Schmaljohann, Siamak Mohammadkhani Shali, Ina Schabram, Christian Stoppe, Paul Cumming, Ralf-Dieter Hilgers, Yoshitaka Kumakura, Mark Coburn, Felix M. Mottaghy, Gerhard Gründer, and Ingo Vernaleken (doi: 10.1016/j.biopsych.2015.11.009). It appears in Biological Psychiatry, volume 80, issue 3 (2016), published by Elsevier.
Journalists wishing to interview the authors may contact Lena Rademacher at Rademacher@snl.uni-luebeck.de.
Biological Psychiatry is the official journal of the Society of Biological Psychiatry, whose purpose is to promote excellence in scientific research and education in fields that investigate the nature, causes, mechanisms and treatments of disorders of thought, emotion, or behavior. Biological Psychiatry is one of the most selective and highly cited journals in the field of psychiatric neuroscience. It is ranked 5th out of 140 Psychiatry titles and 11th out of 256 Neurosciences titles in the Journal Citations Reports® published by Thomson Reuters. The 2015 Impact Factor score for Biological Psychiatry is 11.212. Media contact: Rhiannon Bugno, firstname.lastname@example.org
Rüdiger Labahn | idw - Informationsdienst Wissenschaft
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy