Usefulness of argyrophilic nucleolar organizer regions in detection of lung cells alterations after benzo[a]pyrene instillation1 Uso do AgNOR na detecção de alterações das células do pulmão após o instilação de benzo[a]pireno

Purpose: To verify the relationship between AgNOR expression and lung tissues changes of Wistar rats after pulmonary instillation of benzo[a]pyrene (B[a]P). Methods: Male Rattus norvegicus albinus, Wistar lineage were given a single intrapulmonary instillation of B[a]P at doses of 10 and 20 mg/kg in a volume of approximately 0,3 ml. After 7 and 21 days the rats were killed and the lung slices submitted to a histological technique of AgNOR. AgNOR dots were quantified and the result analyzed by statistical tests; p ≤ 0,05 was considered significant. Results: The mean values of AgNOR dots for the experimental groups 10/7 (1,51±0,86) and 10/21 (1,84±0,13) were statistically different (p = 0,009). Among the groups 20/7 (1,63±0,11) and 20/21 (2,48±0,28) was observed statistically significant difference (p = 0,003). Conclusion: The AgNOR technique can be useful in identification of cells changes induced by B[a]P.