Lung fibrosis and emphysema: divergent responses to a common injury?

Cadmium chloride, administered intratracheally to golden Syrian hamsters, causes an acute lung injury which evolves into a lesion with functional and morphological features of diffuse fibrosis. With simultaneous feeding of a lathyrogen, beta-aminoproprionitrile, this same injury evolves into functional and morphological changes of bullous emphysema. These results suggest that the same lung injury might result in either fibrosis or emphysema, connective tissue synthesis during the healing phase being the critical determinant.