Inhibition of monoamine oxidase B
in the brains of smokers

Fowler JS; Volkow ND; Wang GJ; Pappas N;
Logan J; MacGregor R; Alexoff D; Shea C;
Schlyer D; Wolf AP; Warner D; Zezulkova I; Cilento R
Brookhaven National Laboratory,
Upton, New York 11973, USA.
Nature, 1996 Feb, 379:6567, 733-6


The massive health problem associated with cigarette smoking is exacerbated by the addictive properties of tobacco smoke and the limited success of current approaches to cessation of smoking. Yet little is known about the neuropharmacological actions of cigarette smoke that contribute to smoking behaviour, or why smoking is so prevalent in psychiatric disorders and is associated with a decreased risk of Parkinson's disease. Here we report that brains of living smokers show a 40% decrease in the level of monoamine oxidase B (MAO B; EC relative to non-smokers or former smokers. MAO B is involved in the breakdown of dopamine, a neurotransmitter implicated in reinforcing and motivating behaviours as well as movement. MAO B inhibition is therefore associated with enhanced activity of dopamine, as well as with decreased production of hydrogen peroxide, a source of reactive oxygen species. We propose that reduction of MAO B activity may synergize with nicotine to produce the diverse behavioural and epidemiological effects of smoking.
Yale study
Selegiline and MDMA
Selegiline and nitric oxide
Reversible inhibitors of MAO-b
Selegiline and life-expectancy
Selegiline for longer-lived flies
Low peripheral MAO-b in smokers
Selegiline for cocaine dependence

and further reading

Future Opioids
BLTC Research
Utopian Surgery?
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World

The Good Drug Guide
The Good Drug Guide

The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family