Am. J. Respir. Crit. Care Med., Vol 150, No. 4, Oct 1994, 1101-1107.
Nicotine prevents a reduction in neutrophil filterability induced by cigarette smoke exposure
K Aoshiba, A Nagai and K Konno
First Department of Medicine, Tokyo Women's Medical College, Japan.
Decreased deformability of neutrophils exposed to cigarette smoke is
considered a determinant of neutrophil sequestration within the pulmonary
microvasculature, which may be a risk for the development of pulmonary
emphysema. In this study we examined the effect of nicotine, a major
cigarette component, on the reduction in neutrophil deformability, measured
as cell filterability, after exposed to cigarette smoke. Neutrophils were
exposed to smoke by incubating them in an aqueous solution of smoke
extracts. Filterability of neutrophils was studied by a vertical filtration
technique by measuring their ability to pass through a micropore membrane
and expressed as membrane resistance. There was a negative relationship
between membrane resistance after exposure to whole smoke and the nicotine
content of the cigarettes tested. Whole smoke increased the membrane
resistance less than gas-phase smoke, from which almost all nicotine had
been excluded. Addition of nicotine, glutathione, alpha-tocopherol, thymol,
and erythrocytes prevented the increase in membrane resistance following
gas-phase smoke exposure. Nicotine also protected against an increase in
membrane resistance against the effect of chloramine-T and hydrogen
peroxide, but it provided no protection from superoxide radical generated
from a xanthine-xanthine oxidase mixture of N-
formylmethionylleucylphenylalanine. These results suggest that nicotine
prevents the reduction in neutrophil filterability, probably by scavenging
oxidants present in the cigarette smoke.
