Martín-Valmaseda E M, Sánchez-Yagüe J, Hernández-Hernández A, Llanillo M
Department of Biochemistry and Molecular Biology, University of Salamanca, Spain.
Thromb Haemost. 1998 Oct;80(4):668-76.
To relate the improvement of platelet storage in synthetic media with possible structural changes, we conducted serial studies on the membranes of platelets and microparticles shed during platelet storage for up to 5 days at 4 degrees C either in plasma or in Seto solution. Spontaneous microparticle formation proceeded linearly for up to 2 days in both storage media, although the processes seemed to be different because microparticles from Seto solution had a higher lipid/protein ratio than those released in plasma. Microparticles were heterogeneous structures showing beta-N-acetylhexosaminidase, glucose-6-phosphatase and succinate dehydrogenase activities. After 2-5 days of storage, microparticles contained 60% of total cellular acetylcholinesterase (AChE), were doubly enriched in cholesterol. and showed identical phospholipid profiles but with a decrease in the lipid unsaturation index with respect to fresh platelets. Fluorescence anisotropy studies pointed to a remarkable increase in the deep lipid core fluidity of microparticles during storage of platelets in plasma. With respect to platelets, only those stored in plasma showed significant changes in lipid contents, with a 3-fold decrease in the phospholipid to protein ratio, a decrease in phosphatidylethanolamine (PE) levels and a parallel increase in phosphatidylcholine (PC) percentages in their phospholipid profile, together with a significant reduction in the lipid unsaturation index after 1 day of storage. The fluidity of the negatively charged surface of the platelet membranes decreased in platelets stored for 5 days in both media, whereas the fluidity of the membrane deep core was only increased in platelets stored in plasma. These findings suggest that Seto solution permits better storage of platelets for 5 days than plasma and support the notion that lipid peroxidation could play an important role in the structural changes observed.
为了将合成培养基中血小板储存的改善与可能的结构变化联系起来，我们对血小板和在4℃下于血浆或濑户溶液中储存长达5天的血小板储存期间脱落的微粒的膜进行了系列研究。在两种储存培养基中，自发微粒形成在长达2天内呈线性进行，尽管过程似乎不同，因为来自濑户溶液的微粒比血浆中释放的微粒具有更高的脂质/蛋白质比。微粒是显示β-N-乙酰己糖胺酶、葡萄糖-6-磷酸酶和琥珀酸脱氢酶活性的异质结构。储存2-5天后，微粒含有总细胞乙酰胆碱酯酶（AChE）的60%，胆固醇含量加倍，并显示出相同的磷脂谱，但相对于新鲜血小板，脂质不饱和指数降低。荧光各向异性研究表明，在血浆中储存血小板期间，微粒的深层脂质核心流动性显著增加。就血小板而言，只有储存在血浆中的血小板脂质含量有显著变化，磷脂与蛋白质的比例降低了3倍，磷脂酰乙醇胺（PE）水平降低，磷脂谱中磷脂酰胆碱（PC）百分比平行增加，并且储存1天后脂质不饱和指数显著降低。在两种培养基中储存5天的血小板中，血小板膜带负电荷表面的流动性降低，而膜深层核心的流动性仅在储存在血浆中的血小板中增加。这些发现表明，濑户溶液比血浆更能使血小板储存5天，并支持脂质过氧化可能在观察到的结构变化中起重要作用的观点。
