title: Effects of smokeless tobacco on the buccal mucosa of HMT rats.
abstract: Fifteen male and 15 female HMT rats, 6 months of age, received weekly applications of smokeless tobacco to the buccal mucosa for one year. Hyperorthokeratosis, acanthosis, numerous binucleate spinous cells, and subepithelial connective tissue hyalinization were observed, whereas verrucous carcinoma and squamous cell carcinoma were not seen. Karyotyping revealed that lymphocytes of tobacco-treated as well as control rats had normal chromosome number (2N = 42) and morphology. However, approximately 25% of buccal epithelial cells of the tobacco-treated rats were tetraploid and 5% octaploid, compared to only 11% tetraploid and no octaploid in the controls. Results indicate that the effects of smokeless tobacco on the rat buccal mucosa are similar to those observed in humans and that the mitotic process can be disturbed by tobacco treatment.
authors.affiliation: Pathology Department, Temple University School of Medicine, Philadelphia, PA 19140.
authors.forename: S Y
authors.initials: SY
authors.lastname: Chen
mesh_terms: D000818:Animals; D002277:Carcinoma / Q000209:etiology* / Q000473:pathology; D002869:Chromosome Aberrations / Q000209:etiology; D025063:Chromosome Disorders; D003238:Connective Tissue / Q000473:pathology; D004848:Epithelium / Q000473:pathology; D005260:Female; D007621:Karyotyping; D008214:Lymphocytes / Q000648:ultrastructure; D008297:Male; D009061:Mouth Mucosa / Q000473:pathology*; D009062:Mouth Neoplasms / Q000209:etiology* / Q000473:pathology; D051381:Rats; D011919:Rats, Inbred Strains; D014030:Tobacco, Smokeless