Distribution and ultrastructural characteristics of dark cells in squamous metaplasias of the respiratory tract epithelium. [Rats]

Journal Article · Fri May 01 04:00:00 EDT 1981 · Am. J. Pathol.; (United States)

OSTI ID:7065211

Klein-Szanto, A J.P.; Nettesheim, P; Pine, A; Martin, D

Dark epithelial basal cells were found in both carcinogen-induced and non-carcinogen-induced squamous metaplasias of the tracheal epithelium. Formaldehyde-induced squamous metaplasias exhibited 4% dark cells in the basal layer. Metaplasias induced by vitamin A deficiency and those induced by dimethylbenz(a)anthracene (DMBA) without atypia showed 18-20% basal dark cells. DMBA-induced metaplasias with moderate to severe atypia exhibited 50% basal dark cells. The labeling index of basal cells in metaplastic epithelia, regardless of the inducing agent, was 16-18%, ie, the same as that of the normal esophageal stratified squamous epithelium. The percentage of labeled dark basal cells per total dark cell population was approximately 19% in the non-carcinogen-induced metaplasias and in the DMBA-induced metaplasias without atypia. In the atypical metaplasias induced by DMA this percentage increased to 26. On the basis of ultrastructural observations, five types of dark epithelial cells could be distinguished in the metaplastic epithelia. Each type of squamous metaplasia could thus be recognized by a determined numerical distribution of dark cells in the basal layer and a specific pattern of distribution of the ultrastructurally defined dark cell categories.

• Research Organization: Oak Ridge National Lab., TN
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 7065211
• Journal Information: Am. J. Pathol.; (United States), Journal Name: Am. J. Pathol.; (United States) Vol. 103:2; ISSN AJPAA
• Country of Publication: United States
• Language: English

Related Subjects

560305* -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALDEHYDES
ANIMAL TISSUES
ANIMALS
AROMATICS
BIOLOGICAL EFFECTS
BODY
CONDENSED AROMATICS
DIMETHYLBENZANTHRACENE
DISEASES
ELECTRON MICROSCOPY
EPITHELIUM
FORMALDEHYDE
MAMMALS
MICROSCOPY
MORPHOLOGICAL CHANGES
NEOPLASMS
NUTRITIONAL DEFICIENCY
ORGANIC COMPOUNDS
RATS
RESPIRATORY SYSTEM
RODENTS
TISSUES
TRACHEA
TRANSMISSION ELECTRON MICROSCOPY
ULTRASTRUCTURAL CHANGES
VERTEBRATES
VITAMIN A
VITAMINS