THURSDAY, Sept. 8, 2005 (HealthDay News) -- Smoking appears to disrupt an important enzyme in the lungs, possibly explaining some of the habit's damaging health effects, researchers report.
The study focused on the effect of smoking on monoamine oxidase A, or MAO A, an enzyme that breaks down many compounds that affect blood pressure.
Using a radiotracer to track the enzyme, researchers found that smokers had MAO A levels that were 50 percent lower than nonsmokers, said lead researcher Joanna S. Fowler, program director of the Brookhaven Center for Translational Neuroimaging in Upton, N.Y.
MAO A breaks down many compounds affecting blood pressure, and the lung is a major organ focused on degrading some of these compounds, Fowler said. So lower levels of the enzyme in smokers' lungs could contribute to high blood pressure or pulmonary disease, the study said.
"The effects of smoking on human health are enormous, yet little is known about the pharmacologic effects of smoking on the human body apart from the effects of nicotine," Fowler said.
The findings appear in the September issue of the Journal of Nuclear Medicine.
Smoking accounts for 440,000 deaths each year in the United States, or nearly one of every five deaths, according to the federal Centers for Disease Control and Prevention.
More information
The U.S. Centers for Disease Control and Prevention has more about the dangers of smoking.
