[Effect of inhalations of polyvinylpyridine-N-oxide on the development of experimental silicosis].

Experiments on albino rats showed that polyvinylpyridine-N-oxide (PVNO) inhalations (mol. mass 2000; 9.8 +/- 1.2 and 99 +/- 4 mg/m3 for 7 months) slowed down the course of silicosis developing with a gradual entrance and uniform distribution of dust in the lungs, but proved little effective with a one-time introduction of a large amount of "aggressive" dust because of the difficulty for the drug to reach and penetrate the sclerosed sections of the tissue. Considering low toxicity and an insignificant cumulative effect of PVNO, the electivity of its accumulation in the lungs during inhalation and marked protective action of low doses the authors hold it expedient to employ the inhalation method of administering the polymer for prevention of silicosis, while its use for curative purpose is not recommended.