title: Experimental otitis media with effusion induced by lipopolysaccharide from Klebsiella pneumoniae: mucociliary pathology of the middle ear.
abstract: We inoculated 100 micrograms/ml of lipopolysaccharide (LPS) from Klebsiella pneumoniae into the tympanic cavity of guinea pigs and examined the mucociliary pathology in the middle ear. Serous effusion was observed in the tympanic cavity of every animal on the first, third, and seventh day following the procedure, but the volume of the effusion had decreased to 0.2 ml on day 7. By that time, the ciliary activity in the opening to the eustachian tube within the middle ear had recovered to some extent, but in the middle ear distal to the opening no recovery was apparent. Our results show that cilia close to the eustachian tube play a more significant role in middle ear clearance than those in the middle ear distal to the tube. Compared with our previous study using 10 micron/ml of LPS, this study also demonstrates that inoculations with a higher concentration of LPS induces longer-term middle ear effusions.
mesh_terms: D000818:Animals; D002923:Cilia / Q000473:pathology / Q000648:ultrastructure; D004432:Ear, Middle / Q000473:pathology* / Q000648:ultrastructure; D006168:Guinea Pigs; D007711:Klebsiella pneumoniae; D008070:Lipopolysaccharides / Q000633:toxicity*; D008297:Male; D008854:Microscopy, Electron; D009079:Mucociliary Clearance; D010034:Otitis Media with Effusion / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D013997:Time Factors
chemical_list: D008070:Lipopolysaccharides