Acute effect of smoking on elastaselike esterase activity and immunologic neutrophil elastase levels in bronchoalveolar lavage fluid.

In order to determine the acute effect of smoking on elastase in bronchoalveolar lavage fluid (BAL), we obtained BAL from 30 smokers twice, the first before smoking (after 8 h of abstinence) and the second 2 min to 1 h after the subjects had smoked either 2 or 4 cigarettes. Bronchoalveolar lavage was concentrated 100-fold and was assayed for elastaselike activity against succinyl-trialanyl-p-nitroanilide (SLAPN) as substrate. Elastolytic activity against insoluble 3H-elastin and immunologic neutrophil elastase levels tested with a sensitive enzyme-linked immunosorbent assay were determined in some subjects. No activity against insoluble 3H-elastin was detected using a sensitive assay capable of detecting subnanogram quantities of elastase. Total elastaselike activity in BAL against SLAPN was significantly (p less than 0.02) increased in smokers prior to smoking (47.4 +/- SD 20.2 ng human neutrophil elastase (HNE) equivalents) when compared with BAL from 7 nonsmokers (26.3 +/- SD 13.4 ng HNE); however, there was no significant change in enzyme activity in smokers' BAL after smoking. Assays with EDTA and phenyl-methyl-sulfonyl-fluoride as inhibitors suggested that approximately two thirds of elastaselike activity was due to a metalloprotease and that there was negligible serine protease activity.(ABSTRACT TRUNCATED AT 250 WORDS)