title: Specificity and uniqueness of endothelial cell stress responses.
abstract: The mammalian response to cellular stresses often involves upregulation of certain stress proteins. This response is usually neither cell nor stress specific and sometimes results in cross-protection to other stresses. Endothelial cell (EC) hypoxia-associated proteins (HAP) are a unique set of stress proteins upregulated by exposure to environmental hypoxia. In the present study, the specificity of stress protein upregulation was assessed and any potential cross-protection was evaluated using DNA strand break analysis. EC cultured in 21% or 3% oxygen were exposed to single and combined cellular stresses (0% oxygen, reoxygenation, glucose deprivation, sodium arsenite, heat, or hydrogen peroxide). Although EC can upregulate various stress proteins, the HAP are specifically upregulated only with hypoxia and offer no cross-protection against other cellular stresses. Moreover, induction of other stress proteins does not alter the induction of the HAP or the effects of hypoxia in cultured EC. Thus EC display a unique specificity in regard to the stimulus for upregulation of stress proteins and are distinct from other cell types thus far examined.
authors.affiliation: Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA.
authors.forename: M
authors.initials: M
authors.lastname: Tucci
authors.forename: R J
authors.initials: RJ
authors.lastname: McDonald
authors.forename: R
authors.initials: R
authors.lastname: Aaronson
authors.forename: K K
authors.initials: KK
authors.lastname: Graven
authors.forename: H W
authors.initials: HW
authors.lastname: Farber
mesh_terms: D000818:Animals; D002417:Cattle; D015687:Cell Hypoxia; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000473:pathology; D006360:Heat-Shock Proteins / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D006360:Heat-Shock Proteins