Low monoamine oxidase B in peripheral organs in smokers

Joanna S. Fowler, Jean Logan, Gene Jack Wang, Nora D. Volkow, Frank Telang, Wei Zhu, Dinko Franceschi, Naomi Pappas, Richard Ferrieri, Colleen Shea, Victor Garza, Youwen Xu, David Schlyer, S. John Gatley, Yu Shin Ding, David Alexoff, Donald Warner, Noelwah Netusil, Pauline Carter, Millard JaynePayton King, Paul Vaska

Research output: Contribution to journalArticlepeer-review

73 Scopus citations


One of the major mechanisms for terminating the actions of catecholamines and vasoactive dietary amines is oxidation by monoamine oxidase (MAO). Smokers have been shown to have reduced levels of brain MAO, leading to speculation that MAO inhibition by tobacco smoke may underlie some of the behavioral and epidemiological features of smoking. Because smoking exposes peripheral organs as well as the brain to MAO-inhibitory compounds, we questioned whether smokers would also have reduced MAO levels in peripheral organs. Here we compared MAO B in peripheral organs in nonsmokers and smokers by using positron emission tomography and serial scans with the MAO B-specific radiotracers, L-[11C]deprenyl and deuterium-substituted L-[11C]deprenyl (L-[ 11C]deprenyl-D2). Binding specificity was assessed by using the deuterium isotope effect. We found that smokers have significantly reduced MAO B in peripheral organs, particularly in the heart, lungs, and kidneys, when compared with nonsmokers. Reductions ranged from 33% to 46%. Because MAO B breaks down catecholamines and other physiologically active amines, including those released by nicotine, its inhibition may alter sympathetic tone as well as central neurotransmitter activity, which could contribute to the medical consequences of smoking. In addition, although most of the emphases on the carcinogenic properties of smoke have been placed on the lungs and the upper airways, this finding highlights the fact that multiple organs in the body are also exposed to pharmacologically significant quantities of chemical compounds in tobacco smoke.

Original languageEnglish
Pages (from-to)11600-11605
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number20
StatePublished - 30 Sep 2003
Externally publishedYes


Dive into the research topics of 'Low monoamine oxidase B in peripheral organs in smokers'. Together they form a unique fingerprint.

Cite this