title: Lead inhibits nitric oxide production transiently by mRNA level in murine macrophage cell lines.
abstract: Lead inhibited the production of nitric oxide (NO) in cytokine-induced macrophage cell lines of RAW264 and Mm1. The decrease was revealed in the concentration of lead (0.1-10 micrograms/ml) which did not decrease the viability of these cells. The inhibition was proved to be due to the suppression of an inducible type of NO synthase (iNOS) mRNA expression in RAW264 cells. This suppression was found at 24 h and then recovered to the control level (stimulated with cytokine alone) following culture. In the RAW264 cell line, the time course pattern of NO production corresponded to the iNOS mRNA expression. From these results, the inhibition of NO production by, at least in part, mRNA level could be implicated in lead-caused abnormalities in immune functions.
authors.affiliation: Department of Environmental Biochemistry and Toxicology, School of Pharmaceutical Science, University of Shizuoka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kanematsu
authors.forename: K
authors.initials: K
authors.lastname: Takagi
authors.forename: N
authors.initials: N
authors.lastname: Masuda
authors.forename: Y
authors.initials: Y
authors.lastname: Suketa
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003864:Depression, Chemical; D004790:Enzyme Induction / Q000187:drug effects; D007854:Lead / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis*
chemical_list: D012333:RNA, Messenger; D007854:Lead; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase