Panasenko O M, Arnhold J, Sergienko V I
Research Institute of Physical and Chemical Medicine, Moscow, Russia.
Biofizika. 1998 May-Jun;43(3):463-9.
In order to make a further sight into mechanism of hypochlorite (HOCl/OCl-)-induced lipid peroxidation we investigated the effect of pH of incubation medium on accumulation of lipid peroxidation products and also on kinetics of HOCl/OCl- decay and disappearance of double bonds during incubation of egg yolk phosphatidylcholine liposomes with hypochlorite. On the one hand, the increase in pH values led to decrease of the rate of a reaction of hypochlorite with double bonds of phosphatidylcholine acyl chains and, on the other hand, to increase in accumulation of primary (conjugated dienes and lipid peroxides) and secondary (TBA-reactive substances) products of lipid peroxidation. The present data and our previous results allow to suppose that besides the electrophilic addition of HOCl to double bonds another reaction of HOCl/OCl- with some lipid intermediate occurs that leads to initiation of free radical processes of lipid peroxidation. This reaction increases in velocity as pH rises at least in the range from 6.50 to 8.15. The role of intermediate may be performed by organic hydroperoxides which are known to be present in some proportion in lipid phase in vivo.
为了进一步深入了解次氯酸盐（HOCl/OCl-）诱导脂质过氧化的机制，我们研究了孵育介质的pH值对脂质过氧化产物积累的影响，以及对次氯酸盐（HOCl/OCl-）在蛋黄磷脂酰胆碱脂质体与次氯酸盐孵育过程中的衰减动力学和双键消失的影响。一方面，pH值的升高导致次氯酸盐与磷脂酰胆碱酰链双键反应速率降低，另一方面，导致脂质过氧化的初级产物（共轭二烯和脂质过氧化物）和次级产物（TBA反应性物质）积累增加。目前的数据和我们之前的结果表明，除了HOCl对双键的亲电加成外，HOCl/OCl-还与一些脂质中间体发生另一种反应，从而引发脂质过氧化的自由基过程。至少在6.50至8.15的范围内，该反应速度随着pH升高而增加。中间体的作用可能由有机氢过氧化物来承担，已知在体内脂质相中有机氢过氧化物以一定比例存在。
