Cadmium-chloride-induced air-space enlargement with interstitial pulmonary fibrosis is not associated with destruction of lung elastin. Implications for the pathogenesis of human emphysema

Am Rev Respir Dis. 1988 Apr;137(4):918-23. doi: 10.1164/ajrccm/137.4.918.


To determine whether lung elastin is lost during the evolution of cadmium-induced air-space enlargement with pulmonary fibrosis, the lung elastin of 5- to 7-day-old golden Syrian hamster pups was radiolabeled by giving [3H]valine. At maturity, a single intratracheal instillation of 0.5 ml of 0.025% CdCl2 solution was given. Lung mechanics, histologic examination, and biochemistry were studied 5, 10, 21, 42, 105, and 180 days after the cadmium treatment. The animals developed fibrosis and air-space enlargement with decreased lung volumes, compliance, and forced expiratory flow; their functional residual capacity was increased. The total lung collagen and total lung elastin were increased, but there was no loss of radiolabel in lung elastin. We conclude that CdCl2-induced air-space enlargement with pulmonary fibrosis is not accompanied by loss of neonatally formed lung elastic fibers. We hypothesize that air-space enlargement with fibrosis represents a stereotyped response of the lung to fibrosing injuries, which we hypothesize is due to forces from more fibrotic and atelectatic areas causing overdistension of less abnormal air spaces. The air-space enlargement of fibrosing human diseases such as sarcoidosis and eosinophilic granuloma may have a similar basis. Evidence is reviewed that human centrilobular emphysema may be a form of focal air-space enlargement with interstitial fibrosis; there may be mechanisms in addition to elastase-antielastase imbalance that cause human emphysema.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cadmium
  • Cadmium Chloride
  • Elastin / metabolism*
  • Emphysema / etiology*
  • Forced Expiratory Flow Rates
  • Humans
  • Lung / metabolism*
  • Lung / pathology
  • Organ Size
  • Pulmonary Fibrosis / chemically induced
  • Pulmonary Fibrosis / metabolism*
  • Pulmonary Fibrosis / pathology
  • Pulmonary Fibrosis / physiopathology
  • Total Lung Capacity
  • Vital Capacity


  • Cadmium
  • Elastin
  • Cadmium Chloride