title: Pathological features of rat lung following inhalation and intratracheal instillation of C(60) fullerene.
abstract: We evaluated the pulmonary pathological features of rats that received a single intratracheal instillation and a 4-week inhalation of a fullerene. We used fullerene C(60) (nanom purple; Frontier Carbon Co. Ltd, Japan) in this study. Male Wistar rats received intratracheal dose of 0.1, 0.2, or 1 mg of C(60), and were sacrificed at 3 days, 1 week, 1 month, 3 months, 6 months, and 12 months. In the inhalation study, Wistar rats received C(60) or nickel oxide by whole-body inhalation for 6 h/day, 5 days/week, 4 weeks, and were sacrificed at 3 days, 1 month, and 3 months after the end of exposure. During the observation period, no tumors or granulomas were observed in either study. Histopathological evaluation by the point counting method (PCM) showed that a high dose of C(60) (1 mg) instillation led to a significant increase of areas of inflammation in the early phase (until 1 week). In the inhalation study of the C(60)-exposed group, PCM evaluation showed significant changes in the C(60)-exposed group only at 3 days after exposure; after 1 month, no significant changes were observed. The present study demonstrated that the pulmonary inflammation pattern after exposure to well-characterized C(60) via both intratracheal and inhalation instillation was slight and transient. These results support our previous studies that showed C(60) has no significant adverse effects in intratracheal and inhalation instillation studies.
authors.affiliation: Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Kitakyushu, Fukuoka, Japan. gamisan@med.uoeh-u.ac.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Ogami
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Fujita
authors.forename: Masami
authors.initials: M
authors.lastname: Hirohashi
authors.forename: Takako
authors.initials: T
authors.lastname: Oyabu
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Myojo
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Nishi
authors.forename: Chikara
authors.initials: C
authors.lastname: Kadoya
authors.forename: Motoi
authors.initials: M
authors.lastname: Todoroki
authors.forename: Makoto
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Murakami
authors.forename: Manabu
authors.initials: M
authors.lastname: Shimada
authors.forename: Wei-Ning
authors.initials: WN
authors.lastname: Wang
authors.forename: Naohide
authors.initials: N
authors.lastname: Shinohara
authors.forename: Shigehisa
authors.initials: S
authors.lastname: Endoh
authors.forename: Kunio
authors.initials: K
authors.lastname: Uchida
authors.forename: Junko
authors.initials: J
authors.lastname: Nakanishi
authors.forename: Isamu
authors.initials: I
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D037741:Fullerenes / Q000008:administration & dosage*; D007249:Inflammation / Q000139:chemically induced; D019570:Inhalation Exposure / Q000009:adverse effects*; D008168:Lung / Q000187:drug effects* / Q000473:pathology; D055370:Lung Injury / Q000139:chemically induced*; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry; D019055:No-Observed-Adverse-Effect Level; D010316:Particle Size; D051381:Rats; D017208:Rats, Wistar
chemical_list: D037741:Fullerenes