The acute effect of cigarette smoking on the neutrophil elastase inhibitory capacity of peripheral lung lavage from asymptomatic volunteers.

Cigarette smoke-induced emphysema is thought to involve reduction of antielastolytic capacity, resulting in elevated elastase activity and lung tissue damage. Peripheral lavage collected from ten asymptomatic subjects immediately before and 20 min after smoking two high tar cigarettes was analysed for neutrophil elastase (NE) inhibitory capacity (IC), alpha 1-proteinase inhibitor (PI) function, elastolytic activity and immunoreactive levels of PI and bronchial inhibitor (BI). The only change found was a small fall in mol immunoreactive PI/mol albumin after smoking (approximately 17%, p less than 0.05) which did not affect NEIC, since PI contributed less than 50% of the NEIC. There was often more NEIC than mol BI + functional PI, suggesting the presence of other NE inhibitors. Thoracic computerized tomography scans of eight of these subjects highlighted two with emphysematous regions of lung; lavage from these two subjects contained either undetectable BI or inactive BI and this suggests a protective role for BI in emphysema.