Koerner T A, Cunningham M T, Zhang D S
Department of Pathology, University of Iowa College of Medicine, Iowa City 52242-1087.
Blood Cells. 1992;18(3):481-97; discussion 498-500.
Because of their hemostatic and structural importance and their chemical and physical lability, membrane lipids are likely to be involved in the development of the platelet storage lesion. Chemical analysis using the new method of high-performance liquid chromatography with laser light scattering detection (HPLC-LLS) reveals platelet lipid to be composed of more than 22 individual components, the most abundant of which are phosphatidylcholine (PC), phosphatidylethanolamine (PE), cholesterol (C), sphingomyelin (SM), phosphatidylserine (PS), and phosphatidylinositol (PI). Surprisingly, an asymmetric distribution of these lipids is maintained in the resting platelet with PS concentrated in the inner leaflet of the plasma membrane. The exposure of PS may be important in platelet activation because of its powerful procoagulant effect. Studies of the effect of blood bank storage on platelet lipid composition have repeatedly shown a steady loss of all components, which may be temperature dependent. Studies of platelet factor 3 activity and flow cytometry of stored platelets have revealed the lipid is lost through the process of microvesiculation. Coupled to this storage induced depletion of platelet lipid is a loss of more than half of the potential capacity of lipid-dependent platelet functions by day 5. The most likely underlying mechanism for this loss of lipid mass and functional capacity is lipid peroxidation, a process that could be blocked with antioxidants. Lipid peroxidation may also interfere with other membrane constituents such as glycoprotein IIb/IIIa and the aminophospholipid-specific translocase. Thus, lipid peroxidation should be a major focus in studies aimed at preventing or reversing the platelet storage lesion.
由于其止血和结构重要性以及化学和物理不稳定性，膜脂可能参与血小板储存损伤的发生发展。使用高效液相色谱结合激光散射检测（HPLC-LLS）新方法进行的化学分析表明，血小板脂质由22种以上的单个成分组成，其中最丰富的是磷脂酰胆碱（PC）、磷脂酰乙醇胺（PE）、胆固醇（C）、鞘磷脂（SM）、磷脂酰丝氨酸（PS）和磷脂酰肌醇（PI）。令人惊讶的是，这些脂质在静息血小板中保持不对称分布，PS集中在质膜的内小叶中。由于其强大的促凝血作用，PS的暴露在血小板激活中可能很重要。对血库储存对血小板脂质组成影响的研究反复表明，所有成分都在稳步流失，这可能与温度有关。对储存血小板的血小板因子3活性和流式细胞术的研究表明，脂质通过微囊泡化过程流失。与这种储存诱导的血小板脂质消耗相关的是，到第5天时，脂质依赖性血小板功能的潜在能力丧失了一半以上。脂质质量和功能能力丧失最可能的潜在机制是脂质过氧化，这一过程可以被抗氧化剂阻断。脂质过氧化还可能干扰其他膜成分，如糖蛋白IIb/IIIa和氨基磷脂特异性转位酶。因此，脂质过氧化应该是旨在预防或逆转血小板储存损伤的研究的主要重点。
