This Article Free Full Text Free Free Full Text (Free PDF) Free Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Kaewamatawong, T. Articles by Takano, H. Search for Related Content PubMed PubMed Citation Articles by Kaewamatawong, T. Articles by Takano, H. Social Bookmarking                         What's this?

Acute and Subacute Pulmonary Toxicity of Low Dose of Ultrafine Colloidal Silica Particles in Mice after Intratracheal Instillation

¹ Department of Veterinary Pathology, Tottori University, Minami 4-101, Koyama, Tottori-shi, Tottori 680-8553, Japan
² National Institute for Environmental Studies, Onogama 16-2, Tsukuba 305-8506, Japan

Correspondence: Address correspondence to: Akinori Shimada, Department of Veterinary Pathology, Tottori University, Minami 4-101, Koyama, Tottori-shi, Tottori 680-0945, Japan. E-mail:aki{at}muses.tottori-u.ac.jp

To study the acute and subacute lung toxicity of low dose of ultrafine colloidal silica particles (UFCSs), mice were intratracheally instilled with 0, 0.3, 3, 10, 30 or 100 µg of UFCSs. Cellular and biochemical parameters in bronchoalveolar lavage fluid (BALF), histological alteration and the body weight were determined at 3 days after instillation. Exposure to 30 or 100 µg of UFCSs produced moderate to severe pulmonary inflammation and tissue injury. To investigate the time response, mice were instilled with 30 µg of UFCSs and sacrificed at intervals from 1 to 30 days post-exposure. UFCSs induced moderate pulmonary inflammation and injury on BALF indices at acute period; however, these changes gradually regressed until recovery during the experiment. Concomitant histopathological and laminin immunohistochemical findings generally correlated to BALF data. TUNEL analyses in UFCSs-treated animals showed a significant increase of the apoptotic index in lung parenchyma at all observation times. 8-OHdG expression occurred in lung epithelial cells and activated macrophages, which correlated to lung lesions in UFCSs-treated mice. These findings suggest that instillation of a small dose of UFCSs causes transient acute moderate lung inflammation and tissue damage. Oxidative stress and apoptosis may underlie the lung tissue injury induction.

Key Words: Apoptosis • bronchoalveolar lavage • intratracheal instillation • lung toxicity • oxidative stress • ultrafine colloidal silica

Toxicologic Pathology, Vol. 34, No. 7, 958-965 (2006)
DOI: 10.1080/01926230601094552


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?