title: Effect of long-term methotrexate-induced neutropenia on experimental periodontal lesion in rats.
abstract: The effects of long-term methotrexate (MTX)-induced neutropenia on the periodontal lesion in rats were investigated histologically, histometrically and bacteriologically. A nylon thread was inserted into the interdental gingiva between the 1st and 2nd right maxillary molars of the animals 3 weeks before an application of MTX. The animals were then divided into Groups A and B. Group B were injected intraperitoneally with 1.0 mg/kg of MTX 3 times per week for 9 weeks. Group A received saline as a control. Five animals were killed at the 1st, 3rd, 5th, 7th, and 9th week. In Group A, the neutrophils did not decrease during these 9 weeks. In Group B, however, the neutrophils decreased during the 3rd to 9th week. Whereas the experimental side of Group A showed only moderate alveolar bone resorption between the 7th and 9th week, [in Group B] a marked alveolar bone resorption occurred in Group B occurred in the same period. Alveolar bone loss in the experimental side of Group B was significantly greater (p < 0.01) than in Group A in the 7th to 9th weeks. The percentage of gram-negative rods increased in both control and experimental sides of Group at the 9th week. The results of the present study indicate that neutropenia is induced by a long-term application of MTX in rats and that alveolar bone destruction increases as time goes by in the area where a nylon thread was inserted.
authors.affiliation: Department of Periodontology, School of Dentistry, Aichi-Gakulin University, Nagoya, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Yoshinari
authors.forename: Y
authors.initials: Y
authors.lastname: Kameyama
authors.forename: Y
authors.initials: Y
authors.lastname: Aoyama
authors.forename: H
authors.initials: H
authors.lastname: Nishiyama
authors.forename: T
authors.initials: T
authors.lastname: Noguchi
mesh_terms: D016301:Alveolar Bone Loss / Q000209:etiology* / Q000276:immunology / Q000382:microbiology; D000818:Animals; D003773:Dental Plaque / Q000382:microbiology; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D007958:Leukocyte Count / Q000187:drug effects; D008297:Male; D008727:Methotrexate / Q000633:toxicity; D009503:Neutropenia / Q000139:chemically induced / Q000150:complications*; D010518:Periodontitis / Q000209:etiology* / Q000276:immunology / Q000382:microbiology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D008727:Methotrexate