The Effects of Exposure to Environmental Cigarette Smoke on the Vocal Folds of Rats.

OBJECTIVE

This study aimed to investigate histopathologically and immunohistochemically the effects of environmental smoke on the vocal folds.

METHODS

This study examined 20 healthy Wistar albino rats, which were divided into four groups of five rats. Group 1 was exposed to smoke for 45 days and group 2 for 90 days. Groups 3 and 4 were the respective control groups. The rats in groups 1 and 3 were sacrificed on day 45 and those in groups 2 and 4 on day 90. The larynx specimens were stained with hematoxylin and eosin, and the inflammation, hyperplasia, and metaplasia were evaluated. Ki-67 staining was used for the immunohistochemical analysis.

RESULTS

There was no significant difference in mononuclear cell infiltration between the experimental and control groups (group 1 vs. group 3 P = 0.20, group 2 and 4 P = 0.41) (Table 3), but there was a significant difference between the two experimental groups (P = 0.007). Mild and moderate hyperplasia was seen in groups 1 and 2, respectively.

CONCLUSION

Environmental exposure to cigarette smoke has destructive effects on the vocal folds of rats.