HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 294/1/L87    most recent 00186.2007v1 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 ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mercer, R. R. Articles by Castranova, V. Search for Related Content PubMed PubMed Citation Articles by Mercer, R. R. Articles by Castranova, V.

Alteration of deposition pattern and pulmonary response as a result of improved dispersion of aspirated single-walled carbon nanotubes in a mouse model

¹Pathology and Physiology Research Branch, Health Effect Laboratory Division, National Institute for Occupational Safety and Health, Morgantown; and ²Department of Physiology and Pharmacology, West Virginia University, Morgantown, West Virginia

Submitted 10 May 2007 ; accepted in final form 11 November 2007

Nanoparticles have a fundamental dimension of <100 nm. However, on suspension in media, agglomerates of nanoparticles are the more common structure. This is particularly evident in prior intratracheal instillation or aspiration studies of single-walled carbon nanotubes (SWCNT), in which granulomatous lesions encased by epithelioid macrophages were produced by large agglomerates. In this study, we tested the hypothesis of whether exposure to more dispersed SWCNT structures would alter pulmonary distribution and response. A dispersed preparation of single-walled carbon nanotubes (DSWCNT) with a mean diameter of 0.69 µm was given by pharyngeal aspiration to C57BL/6 mice. Electron microscopy demonstrated a highly dispersed, interstitial distribution of DSWCNT deposits by 1 day postexposure. Deposits were generally <1 µm. Macrophage phagocytosis of DSWCNT was rarely observed at any time point. Lung responses were studied by lavage and morphometry at 1 h, 1 day, 7 day, and 1 mo after a single DSWCNT exposure of 10 µg/mouse. Lung sections and lavage cells demonstrated an early, transient neutrophilic and inflammatory phase that rapidly resolved and was similar to that observed with large agglomerates. No granulomatous lesions or epithelioid macrophages were detected. Morphometric measurement of Sirius red staining was used to assess the connective tissue response. The average thickness of connective tissue in alveolar regions was 0.10 ± 0.02, 0.09 ± 0.02, 0.10 ± 0.01, 0.48 ± 0.04, and 0.88 ± 0.19 µm for PBS and 1-h, 1-day, 7-day, and 1-mo postexposure groups, respectively. The results demonstrate that dispersed SWCNT are rapidly incorporated into the alveolar interstitium and that they produce an increase in collagen deposition.

toxicology; nanoparticles; particulates; emerging technologies; lung injury

This article has been cited by other articles:

				A. A. Shvedova, E. Kisin, A. R. Murray, V. J. Johnson, O. Gorelik, S. Arepalli, A. F. Hubbs, R. R. Mercer, P. Keohavong, N. Sussman, et al. Inhalation vs. aspiration of single-walled carbon nanotubes in C57BL/6 mice: inflammation, fibrosis, oxidative stress, and mutagenesis Am J Physiol Lung Cell Mol Physiol, October 1, 2008; 295(4): L552 - L565. [Abstract] [Full Text] [PDF]

				J. W. Card, D. C. Zeldin, J. C. Bonner, and E. R. Nestmann Pulmonary applications and toxicity of engineered nanoparticles Am J Physiol Lung Cell Mol Physiol, September 1, 2008; 295(3): L400 - L411. [Abstract] [Full Text] [PDF]