Origin of bronchial and pulmonary elastic fibers and their role in some pathological events

The purpose of this contribution is to place a higher value on the existence of a turn-over of bronchial and pulmonary elastic fibers: the former would derive from the smooth muscle cells of the bronchial wall, the latter from the interstitial myofibroblasts of the alveolar septa. The reduction of the number of the elastic fibers in the bronchial wall during chronic atrophic bronchitis depend on the atrophy of the bronchial smooth muscle cells; in the alveolar septa the hyperplasia of the elastic fibers during pulmonary fibroses depend on the myofibroblastic proliferation, while the reduction of the elastic fibers number during pulmonary enphysema depend on the reduction in the number of myofibroblasts.