title: Assessment of proliferative activity in type II pneumocytes after inhalation of NO2 by AgNOR-analysis.
abstract: Adult male Sprague Dawley rats were exposed to 0.8, 5 and 10 ppm NO, alternatively for 1 or 3 days. After exposure the proliferative activity of the airway epithelium was assessed by means of BrdU incorporation and AgNOR-analysis at three different airway levels--in the bronchial, the bronchiolar epithelium and in Type 2 cells. The BrdU-labeling index (BrdU-LI), and AgNOR-number (AgNOR-N) were used to quantify the epithelial proliferation. Cytologic specimens of Type II cells showed a significant increase of the AgNOR-number and BrdU-LI after exposure to 5 ppm NO2 for 3 days and 10 ppm for 1 and 3 days. In the bronchiolar epithelium both, the AgNOR-number and BrdU-LI were significantly elevated in all the exposure groups. In the bronchial epithelium a significant response of the AgNOR-number was found after exposure to 10 ppm for 3 days. The correlation between AgNOR-number and BrdU-LI was 0.78 (p < 0.005).
authors.affiliation: Department of Pathology, Philipps-University Marburg/Lahn, Germany.
authors.forename: P J
authors.initials: PJ
authors.lastname: Barth
authors.forename: B
authors.initials: B
authors.lastname: Müller
authors.forename: U
authors.initials: U
authors.lastname: Wagner
authors.forename: A
authors.initials: A
authors.lastname: Bittinger
mesh_terms: D000280:Administration, Inhalation; D000818:Animals; D001973:Bromodeoxyuridine / Q000032:analysis / Q000378:metabolism; D001980:Bronchi / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006651:Histocytochemistry; D008297:Male; D009585:Nitrogen Dioxide / Q000008:administration & dosage / Q000633:toxicity*; D009697:Nucleolus Organizer Region / Q000737:chemistry / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D012834:Silver / Q000032:analysis; D016622:Silver Staining
chemical_list: D012834:Silver; D001973:Bromodeoxyuridine; D009585:Nitrogen Dioxide