title: Expression of clara cell secretory protein in the lungs of rats exposed to crystalline silica in vivo.
abstract: It has been theorized that Clara cell secretion protein (CCSP) plays a critical role in regulating the acute inflammatory response in the lung. We hypothesized that CCSP is also related to lung injury induced by occupational dust. The present study was conducted to investigate the time course of the expression of CCSP in lungs exposed to crystalline silica in vivo. Male Wistar rats were administered 1 mg or 2 mg of silica suspended in saline by a single intratracheal instillation and were sacrificed at 3 d, 1 wk, 1 month, 3 months and 6 months of recovery time. The expression of CCSP was observed by RT-PCR and western blot analysis. Exposure to 2 mg of silica decreased in levels of CCSP mRNA at 3 d, 1 wk, 1 month and 6 months following intratracheal instillation. The protein level of CCSP in silica-exposed rats was decreased at 3 d, 7 d and 1 month after a single instillation of 2 mg. The decreases in CCSP at the acute phase in this experiment suggest that CCSP may regulate the acute injury of the lung exposed to silica.
authors.affiliation: Institute of Industrial and Ecological Sciences, University of Occupational and Environmental Health. yasuom@med.uoeh-u.ac.jp
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Hiroko
authors.initials: H
authors.lastname: Nagatomo
authors.forename: Masami
authors.initials: M
authors.lastname: Hirohashi
authors.forename: Takako
authors.initials: T
authors.lastname: Oyabu
authors.forename: Akira
authors.initials: A
authors.lastname: Ogami
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamato
authors.forename: Kaori
authors.initials: K
authors.lastname: Kuroda
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Obata
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Higashi
authors.forename: Isamu
authors.initials: I
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D019570:Inhalation Exposure; D007564:Japan; D008297:Male; D011014:Pneumonia / Q000139:chemically induced* / Q000503:physiopathology; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012822:Silicon Dioxide / Q000008:administration & dosage / Q000633:toxicity*; D014598:Uteroglobin / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D012333:RNA, Messenger; D012822:Silicon Dioxide; D014598:Uteroglobin