Brain chemical said to play role in cigarette addiction. Scientists have found that an ingredient in tobacco smoke obstructs the action of monoamine oxidase B, a dopamine-destroying enzyme.
Addictive drugs increase levels of the chemical neurotransmitter dopamine.
The MAO B inhibition may be related to a predisposition for multiple addictions among some people. Brain chemical said to play role in cigarette addiction. Fowler JS, et. Inhibition of monoamine oxidase B in the brains of smokers.