Alterações celulares em figado e pulmão de camundongos tratados com dimetilnitrosamina

AUTOR(ES)
DATA DE PUBLICAÇÃO

1980

RESUMO

Ninety one mice (42 males and 49 females) received dimethylnitrosamine (DMN) in the drinking water, ad libitum during six months. The concentration of DMN in the water varied from: a) 17 ppm (parts per million) during the first month to, b) 10,6 ppm during the other five months. DMN produces several changes in hepatocyte nuclei, as seen by Feulgen s reaction. Dissolution of its chromocenters (constitutive heterochromatin) is one of the alterations described. There is also a considerable increase in nuclear and nucleolar volumes (especially in the last one). Simultaneously, cytophotometric measurements revealed modifications in the distribution patterns of Feulgen-DNA values of these nuclei. Besides the hepatic modification, DMN caused the development of primary malignant tumors in the lungs. Actually, all the animals that survived to 6 months of treatment, showed lung tumors. They were classified as adenocarcinomas derived from outgrowths of the epithelium of small bronchioles. Cytophotometric analysis performed in two of these tumors showed the occurrence of polyploidy in tumoral parenchyma. The data are discussed in view of recent findings concerning DMN mode of action and cancer development. Makino s stem line cell theory which has important implications for tumor therapy, is also discussed.

ASSUNTO(S)

testes funcionais hepaticos pulmões camundongos

ACESSO AO ARTIGO

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