Differential Distribution of Ciliated Epithelial Cells in the Trachea of Hamsters: Implications for Studies of Pathogenesis

Abstract

The morphology of the inner aspect of the adult hamster trachea was examined by scanning electron microscopy. Relatively large patches of unciliated cells were observed in the epithelial layer. The patches, which covered several hundreds to thousands of square microns, were most conspicuous on the ventral surface of the trachea, especially in the middle third. The frequency of these areas of unciliated cells, both isolated and in patches, was much greater in hamsters than in mice, rats, or cats. Greatest ciliation in the hamster trachea was observed over the strip of trachealis muscle between the open ends of the cartilaginous rings. Areas with the heaviest ciliation also had the greatest activity of cellular metabolism, as measured by the tetrazolium reduction assay. The attachment of tritium-labeled cells of Mycoplasma pneumoniae was inversely correlated with extensive ciliation, since the greatest numbers of counts were found on the middle third and ventral regions of the tracheal surface. The results of this study suggest that the regional differences in ciliation of respiratory epithelium in hamsters may influence studies of pathogenesis and isolation of M. pneumoniae and that these differences should therefore be considered and controlled in the experimental design.

Elevated Oxygen Fraction Reduces Cilial Abundance in Explanted Human Bronchial Tissue

“…For example, in the context of oxygen toxicity the elevated metabolic rate in small mammals [29] is likely to be significant. In addition, there are practical issues with at least some commonly used animals: rat and hamster respiratory tracts have poor ciliary coverage, as well as the phenomenon of ciliary banding in relation to tracheal cartilage [30][31][32]. Our findings on the effects of hyperoxia on cilial abundance are consistent with previous data from rat tracheal tissue and support other reports that describe the detrimental effects on cilial abundance and function of high inspired oxygen fraction when administered over sustained periods.…”

Effect of carbon tetrachloride on hamster tracheal epithelial cells

“…This study demonstrated that intraperitoneal administration of CCI 4 produces different degrees of injury in the upper and lower trachea. Gabridge et al (1977), using nitroblue tetrazolium staining of trachéal epithelial cells in hamster, reported that the metabolic activity of trachéal epithelial cells was different in various rings of trachea. Nitroblue tetrazolium reduction was employed as an indicator of "overall metabolic (dehydrogenase) activity" and was found to be greatest in the lower trachea.…”

Role of spatial heterogeneity in the collective dynamics of cilia beating in a minimal one-dimensional model

“…In cultured and in vivo airways epithelium tissues, cilia patches are heterogeneously distributed over the surface [15,16]. For example, observations performed on human bronchial epithelium cultures show that cilia are distributed in clusters containing ∼ 100 − 200 cilia [17], and that these clusters are separated in a random manner.…”