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

Search MEDLINE/PubMed


  • Title: The induction and suppression of prostaglandin H2 synthase (cyclooxygenase) in human monocytes.
    Author: Fu JY, Masferrer JL, Seibert K, Raz A, Needleman P.
    Journal: J Biol Chem; 1990 Oct 05; 265(28):16737-40. PubMed ID: 2120205.
    Abstract:
    We report here that the bacterial lipopolysaccharide endotoxin induces human blood monocytes in a time- and dose-dependent manner to release prodigious amounts of prostaglandins with thromboxane A2, the major metabolite formed. Cells responded to as little as 1 ng/ml lipopolysaccharide to release prostaglandin E2 and thromboxane A2 with maximal stimulation at 10 micrograms/ml. Lipopolysaccharide was found to induce increased activity of cyclooxygenase enzyme without affecting the activities of phospholipase and thromboxane synthase or the formation of 5-lipoxygenase products (e.g. leukotriene B4). The glucocorticoid dexamethasone completely blocked the lipopolysaccharide-induced prostanoid release by inhibiting the activity of monocyte cyclooxygenase. Dexamethasone did not affect phospholipase and thromboxane synthase activities or leukotriene formation. Immunoprecipitation of [35S]methionine-labeled cyclooxygenase confirmed that the effect of lipopolysaccharide and dexamethasone on the monocyte prostanoid production could be attributed to an increase or decrease, respectively, in cellular cyclooxygenase de novo synthesis.
    [Abstract] [Full Text] [Related] [New Search]