[Endogenous factors in the development of emphysema].

The relationship between the development of pulmonary emphysema and the presence of proteolytic enzymes with elastolytic properties released by polymorphonuclear leukocytes or by alveolar macrophages is briefly reviewed. The possible role of various antiproteolytic substances present in the lung is also described. The pathogenesis of pulmonary emphysema is discussed in the light of hypotheses recently put forward implicating an excess of proteolytic factors and/or a relative or absolute lack of protection substances.