[Correlation between changes in lungs caused by industrial dusts and the composition of amino acids in blood plasma. I. Experimental animal studies].

Animals, used for experiments, were intoxicated intratracheally with a suspension of grinding, ceramic or welding dust, in a NaCl solution. These studies demonstrated that the ceramic and welding dusts, used in the experiment, showed a rather great biological activity. This has been proved by the increased weight of dried lungs, and increased total content of some aminoacids in lungs, e.g. hydroxyproline, which is thought to be a reliable index of fibrosis of the pulmonary tissue, as well as of the change in the morphological structure of lungs. Parrallel to the mentioned changes of the lungs, the content of free aminoacids in the animals blood plasma has been remarkably reduced. The results described in this paper prove that there is a dependence between the content of aminoacids in the blood plasma and the changes in lungs caused by dust.