These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Excitatory and inhibitory actions of isoprostanes in human and canine airway smooth muscle.
    Author: Janssen LJ, Premji M, Netherton S, Catalli A, Cox G, Keshavjee S, Crankshaw DJ.
    Journal: J Pharmacol Exp Ther; 2000 Nov; 295(2):506-11. PubMed ID: 11046082.
    Abstract:
    Isoprostanes are generated nonenzymatically during free radical-mediated lipid peroxidation, and are used clinically and experimentally as markers of oxidative stress. However, their biological effects are poorly understood. We examined the effects of seven different 8-isoprostanes in human and canine airway smooth muscles. In large order airways (carina) of the human, several isoprostanes evoked powerful contractions, with 8-iso-prostaglandin (PG) E(2), 8-iso-PGF(1 alpha), and 8-iso-PGF(2 alpha) being the most efficacious (and with logEC(50) values of 7.0, 5.9, and 6.2 microM, respectively). These contractions were sensitive to the prostanoid TP receptor antagonist ICI 192,605 (0.1-1 microM), but not the EP prostanoid receptor antagonist AH-6809 (50 microM), or the leukotriene receptor antagonists monteleukast or ICI 198,615 (both 1 microM). Qualitatively similar results were obtained in small order human airways (<2 mm o.d.), except that the isoprostanes were generally slightly less potent. None of the isoprostanes had any marked excitatory effect in canine airways. In carbachol-preconstricted tissues (pretreated with ICI 192,605 to block any potential contraction), several isoprostanes completely relaxed canine airways: 8-iso-PGE(1), 8-iso-PGE(2), and 8-iso-PGF(3 alpha) were the most potent, with logIC(50) values of 6.9, 6.9, and 5.7, respectively. Only 8-iso-PGF(3 alpha) relaxed human airways (logIC(50) = 4.9). Our results show that several 8-isoprostanes are highly biologically active in human and canine airways, evoking both excitatory and/or inhibitory effects, and that these effects are compound, species, and tissue dependent.
    [Abstract] [Full Text] [Related] [New Search]