Posted by Ron Hill on May 22, 2003, at 19:53:36
In reply to Re: Mirapex » Caleb462, posted by Jack Smith on May 22, 2003, at 12:43:09
> > For instance, tobacco smokers have a much lower chance of developing alzheimers disease.
>
> I knew there was something good about my smoking habit. If only people would stop suing so the price wouldn't keep going up.Hey Jack,
Here is another tidbit regarding cigarette smoke that I found interesting the first time I saw it. Separate and distinct from the effects of nicotine, cigarette smoke contains a compound (2-Naphthylamine) that functions as both an MAOI-A and an MAOI-B. The resulting upward influence on dopamine levels is thought by some to account for the markedly lower incidence of Parkinson's among smokers than the incidence found in the general population. It seems a shame that 2-Naphthylamine is also carcinogenic.
2-Naphthylamine, a compound found in cigarette smoke, decreases both monoamine oxidase A and B catalytic activity.
Hauptmann N, Shih JC.
Department of Molecular Pharmacology and Toxicology, School of Pharmacy, University of Southern California, Los Angeles, USA. hauptman@neotherapeutics.com
Cigarette smokers exhibit a lower monoamine oxidase (MAO; EC 1.4.3.4) activity than nonsmokers. MAO is located in the outer membrane of mitochondria and exists as two isoenzymes, MAO A and B. MAO A prefers 5-hydroxytryptamine (serotonin), and MAO B prefers phenylethylamine (PEA) as substrate. Dopamine is a substrate for both forms. 2-Naphthylamine is a carcinogen found in high concentrations in cigarette smoke. The results of this study show that 2-naphthylamine has the ability to inhibit mouse brain MAO A and B in vitro by mixed type inhibition (competitive and non-competitive). The Ki for MAO A was determined to be 52.0 microM and for MAO B 40.2 microM. The inhibitory effect of 2-naphthylamine on both MAO A and B catalytic activity, supports the hypothesis that smoking decreases MAO activity in vivo, instead that smokers with lower MAO activity are more prone to become a smoker.
PMID: 11233991 [PubMed - indexed for MEDLINE]
poster:Ron Hill
thread:228132
URL: http://www.dr-bob.org/babble/20030520/msgs/228438.html