title: The effect of external stimuli on rat middle ear epithelium in culture. Extracellular carbon dioxide concentration.
abstract: Serially cultivated rat middle ear epithelium was studied under exposure to various concentrations of carbon dioxide. Three experiments were performed exposing the epithelium to a gaseous environment containing 5 or 10% CO2 or to an atmosphere almost devoid of CO2. Oxygen was maintained constant at 20% and nitrogen was additionally supplied. Cells exposed at 0% CO2 showed a remarkably different morphology compared with the cultures at 5 and 10% CO2, cells could become extremely large at 0% CO2, also showing a great variation in shape and cell size within the culture. Proliferation was significantly impaired at 0% CO2 vis-à-vis the 5 and 10% experiments. Terminal differentiation, however, was not influenced by the different CO2 concentrations, indicating that in vitro, variation in CO2 concentration is of no importance regarding a possible differentiation of middle ear epithelium into a cornifying epithelium.
authors.affiliation: ENT Department, University Hospital Leiden, The Netherlands.
authors.forename: H W
authors.initials: HW
authors.lastname: Lutgert
authors.forename: C A
authors.initials: CA
authors.lastname: van Blitterswijk
authors.forename: J J
authors.initials: JJ
authors.lastname: Grote
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000494:pharmacology*; D002452:Cell Count; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D004432:Ear, Middle / Q000166:cytology*; D004847:Epithelial Cells; D066298:In Vitro Techniques; D008297:Male; D008855:Microscopy, Electron, Scanning; D051381:Rats
chemical_list: D002245:Carbon Dioxide