Ischiropoulos H, Zhu L, Beckman J S
Department of Anesthesiology, University of Alabama, Birmingham 35294.
Arch Biochem Biophys. 1992 Nov 1;298(2):446-51. doi: 10.1016/0003-9861(92)90433-w.
Peroxynitrite formation by rat alveolar macrophages activated with phorbol 12-myristate 13-acetate was assayed by the Cu,Zn superoxide dismutase-catalyzed nitration of 4-hydroxyphenylacetate. The inhibitor of nitric oxide synthesis N-methyl-L-arginine prevented the Cu,Zn superoxide dismutase-catalyzed nitration of 4-hydroxyphenylacetate by stimulated macrophages, while Cu-depleted Zn superoxide dismutase did not catalyze the formation of 3-nitro-4-hydroxyphenylacetate either in vitro or in the presence of activated macrophages. The rate of phenolic nitration by activated macrophages was 9 +/- 2 pmol x 10(6) cells-1 x min-1 (mean +/- STD). Only 8% of synthetic peroxynitrite was trapped by superoxide dismutase, which suggested that the rate of peroxynitrite formation may have been as high as 0.11 nmol x 10(6) cells-1 x min-1. This upper estimate was consistent with N-methyl-L-arginine increasing the amount of superoxide detected with cytochrome c by 0.12 nmol x 10(6) cells-1 x min-1. The rate of nitrite and nitrate accumulation was 0.10 +/- 0.001 nmol x 10(6) cells-1 x min-1, suggesting that the majority of nitric oxide produced by activated macrophages may have been converted to peroxynitrite. The formation of a relatively long lived, strong oxidant from the reaction of nitric oxide and superoxide in activated macrophages may contribute to inflammatory cell-mediated tissue injury.
用佛波醇12 -肉豆蔻酸酯13 -乙酸酯激活的大鼠肺泡巨噬细胞中过氧亚硝酸盐的形成，通过铜锌超氧化物歧化酶催化的4 -羟基苯乙酸硝化反应来测定。一氧化氮合成抑制剂N -甲基-L -精氨酸可阻止刺激后的巨噬细胞对4 -羟基苯乙酸进行铜锌超氧化物歧化酶催化的硝化反应，而缺铜的锌超氧化物歧化酶在体外或存在活化巨噬细胞的情况下均不催化3 -硝基-4 -羟基苯乙酸的形成。活化巨噬细胞的酚类硝化速率为9±2 pmol×10⁶细胞⁻¹×min⁻¹（平均值±标准差）。超氧化物歧化酶仅捕获了8%的合成过氧亚硝酸盐，这表明过氧亚硝酸盐的形成速率可能高达0.11 nmol×10⁶细胞⁻¹×min⁻¹。这个上限估计与N -甲基-L -精氨酸使细胞色素c检测到的超氧化物量增加0.12 nmol×10⁶细胞⁻¹×min⁻¹一致。亚硝酸盐和硝酸盐的积累速率为0.10±0.001 nmol×10⁶细胞⁻¹×min⁻¹，这表明活化巨噬细胞产生的大部分一氧化氮可能已转化为过氧亚硝酸盐。活化巨噬细胞中一氧化氮与超氧化物反应形成相对稳定的强氧化剂，可能会导致炎症细胞介导的组织损伤。
