title: Decreased level of lysozyme in rabbit lung lavage fluid after inhalation of low nickel concentrations.
abstract: Six rabbits were exposed for 4 months (5 days/week, 6 h/day) and 6 rabbits for 8 months to approx. 0.1 mg/m3 of metallic nickel dust (U.S. threshold limit value (TLV) 1 mg/m3). Another 8 rabbits were exposed for 4-6 weeks (5 days/week, 6 h/day) to 0.3 mg/m3 (as Ni) of nickel chloride (U.S. TLV 0.1 mg/m3). After exposure lungs were lavaged. Concentration of lysozyme in the lavage fluid was estimated with the lyso-plate technique (agar plates with heat-killed Micrococcus lysodeikticus) after macrophages had been removed. All 3 exposed groups had markedly lower concentrations of lysozyme than corresponding controls. Mean values in controls and exposed rabbits were: for 4 months metallic nickel dust exposure 2.3 and less than or equal to 0.04 microgram/ml; for 8 months metallic nickel dust exposure 1.4 and less than or equal to 0.5 microgram/ml; and for nickel chloride exposure 1.9 and less than or equal to 0.4 microgram/ml.
mesh_terms: D000818:Animals; D008168:Lung / Q000187:drug effects / Q000201:enzymology*; D008264:Macrophages / Q000187:drug effects; D008297:Male; D009113:Muramidase / Q000032:analysis*; D009532:Nickel / Q000633:toxicity*; D011817:Rabbits; D007507:Therapeutic Irrigation
chemical_list: D009532:Nickel; D009113:Muramidase