Abstract

Non-specific pulmonary diseases of the lung new constitute one of the most important medical, social and economic problems of modern civilization. For the causes of non-specific pulmonary diseases it is well documented that the single basic or common property is hypersecretion of branchial mucus. Also it seems to be acceptable that the disturbance of mucus secretion plays a role in the pathogenesis of pulmonary diseases. Hu(1966) in our laboratory revealed that injury (stress) induced marked regressive changes of respiratory mucosa and decreased mucus secretion. Sue (1969) confirmed by autoradiographic method that injury affect profoundly the respiratory tract and bring forth regressive changes in the ciliated epithelium, goblet cells and mixed glands, and reduce mucus secretion due to the interference of uptake of 35S (Na₂³⁵SO₄) into the goblet cells. Kim (1966) demonstrated the amounts of RNA of the lung tissues is decreased by injury. Therefore the authors performed the autoradiographic observation of early incorporation of L- leucine-U-l4C into the epithelium both of the main bronchus and bronchioles in both of normal and∼burned mice in order to confirm that injury may affect on protein metabolism of the epithelium of those tissues. The results were as follows: In the burned mice, the incorporation rate of L-leucine-U-l4C into the epithelial cells of the main bronchus decreased, and that of the bronchioles increased and reached its maximum later than those of normal mice.