An 18-month study of the effects on hamster lungs of intratracheally administered XXXX neutrophil elastase.

@entity1 @entity68 @entity548 @entity2415 @entity329 @entity13789 @entity130
A study was made of the evolution of @entity2415 and @entity130 induced in the lungs of male golden @entity329 by a single intratracheal injection of 350 micrograms @entity1 neutrophil elastase ( @entity13789 ). Saline control and @entity13789 -treated groups of 8 animals were studied 1, 3, 6, 12, and 18 months posttreatment. @entity13789 treatment caused a significant increase in all lung volumes and a significant decrease in maximum expiratory flows at all study times. The mean linear intercept (MLI) values of the left lung were significantly increased over control values. There was no progression with time in MLI values, lung volumes, or lung compliance. Secretory-cell metaplasia was present at 1 month and persisted throughout the study. The @entity13789 -treated lungs showed clusters of ferric @entity68 -containing macrophages in the terminal airspaces. The amount of @entity68 in the lungs, determined morphometrically, was greatest at 1 month, was decreased by 6 months, and then did not change further to 18 months. At 18 months the amount of @entity68 was still significantly above control amounts. We conclude that the airway and parenchymal lesions induced by @entity13789 persist without progression for 18 months. Clearance of ferric @entity68 , which was probably a result of the @entity548 induced by @entity13789 treatment, continued for 6 months with no evident subsequent clearance.
