Dikalov S, Skatchkov M, Bassenge E
Institute of Chemical Kinetics & Combustion, Novosibirsk, Russia.
Biochem Biophys Res Commun. 1997 Feb 24;231(3):701-4. doi: 10.1006/bbrc.1997.6174.
The reactions of new spin trap 1-hydroxy-3-carboxy-pyrrolidine (CP-H) with superoxide radicals and peroxynitrite were studied. The rate constants were determined as 3.2 x 10(3) and 4.5 x 10(9) M-1s-1, respectively. It was found that 2mM of spin trap CP-H or 1-hydroxy-2,2,6,6-tetramethyl-4-oxo-piperidine (TEMPONE-H) provide almost the same spin trapping efficacy. In contrast to TEMPONE-H the reaction of CP-H with peroxynitrite was inhibited by 20 mM DMSO. This simplifies the quantification of peroxynitrite formation. During the reaction of CP-H and TEMPONE-H with superoxide radicals or peroxynitrite the stable nitroxide radicals 3-carboxy-proxyl (CP) and 2,2,6,6-tetramethyl-4-oxo-piperidinoxyl (TEMPONE) are formed. It was found that the rate of reduction of CP by glutathione or by smooth muscle cells was two-fold slower and the reduction of CP by ascorbate was 66-fold slower than corresponding rates of reduction of TEMPONE. Therefore quantification of the formation of superoxide radicals and of peroxynitrite by CP-H is much less hindered by a variety of biological reductants than in case of TEMPONE-H. Thus, CP-H is more suitable for spin trapping of superoxide radicals and peroxynitrite in biological systems than the TEMPONE-H.
研究了新型自旋捕集剂1-羟基-3-羧基吡咯烷（CP-H）与超氧自由基和过氧亚硝酸盐的反应。测定的速率常数分别为3.2×10³和4.5×10⁹ M⁻¹s⁻¹。发现2 mM的自旋捕集剂CP-H或1-羟基-2,2,6,6-四甲基-4-氧代哌啶（TEMPONE-H）具有几乎相同的自旋捕集效率。与TEMPONE-H不同，CP-H与过氧亚硝酸盐的反应受到20 mM二甲基亚砜（DMSO）的抑制。这简化了过氧亚硝酸盐形成的定量分析。在CP-H和TEMPONE-H与超氧自由基或过氧亚硝酸盐的反应过程中，会形成稳定的氮氧自由基3-羧基-脯氨酰自由基（CP）和2,2,6,6-四甲基-4-氧代哌啶氮氧自由基（TEMPONE）。研究发现，谷胱甘肽或平滑肌细胞使CP还原的速率比使TEMPONE还原的相应速率慢两倍，而抗坏血酸使CP还原的速率比使TEMPONE还原的相应速率慢66倍。因此，与TEMPONE-H相比，CP-H对超氧自由基和过氧亚硝酸盐形成的定量分析受多种生物还原剂的干扰要小得多。因此，在生物系统中，CP-H比TEMPONE-H更适合用于自旋捕集超氧自由基和过氧亚硝酸盐。
