中文摘要：

目的：探讨血浆脂蛋白上鞘氨醇-1-磷酸（S1P）和磷脂转运蛋白（PLTP）的相互作用及机制。方法：检测雄性10周龄PLTP转基因（PLTP-Tg）及野生型（WT）小鼠血浆S1P和脂蛋白上S1P含量，转运实验检测PLTP对S1P的转运作用，免疫印迹检测S1P载体载脂蛋白M（ apoM）含量。结果：PLTP-Tg小鼠血浆S1P含量较WT小鼠下降21．1％（P＜0．01），高密度脂蛋白（HDL）组分上S1P含量下降约35．1％，而低密度脂蛋白（LDL）组分上S1P比例则增加了127．4％。转运实验表明，在37℃时D-Hanks 缓冲液中PLTP能够促进S1P从红细胞转运至重组脂质体。 PLTP-Tg小鼠血浆中apoM含量与WT小鼠比较无变化。结论：生理水平PLTP对保持HDL上S1P含量有重要意义，过表达PLTP可显著降低HDL上S1P，同时升高LDL上S1P，其机制可能与PLTP介导S1P转运有关。

英文摘要：

[ABSTRACT]AIM：Toinvestigatetheinteractionandthemechanismofsphingosine-1-phosphate（S1P）and phospholipid transfer protein （PLTP） in lipoprotein.METHODS：The S1P content in the plasma and lipoprotein from 10-week-old PLTP transgenic （PLTP-Tg） mice and wild-type （WT） mice （n=8 each） was assayed.The transport of S1P by PLTP was determined by S1P transfer assay.The content of specific S1P carrier, apolipoprotein M, was detected by West-ern blotting.RESULTS：Plasma S1P contents were decreased by 21.1%in PLTP-Tg mice compared with WT mice.S1P content in high-density lipoprotein （ HDL） fraction （ HDL-S1P） from PLTP-Tg mice was decreased by 35.1% compared with WT mice, whereas the S1P in low-density lipoprotein （LDL） fraction （LDL-S1P） was increased by 127.4%.The re-sults of S1P transfer assay indicated that PLTP facilitated S 1P transport from erythrocyte to recombinant liposome at 37℃in D-Hanks buffer solution .The plasma content of apolipoprotein M was not changed in PLTP-Tg mice compared with WT mice.CONCLUSION：PLTP is a key factor to maintain plasma HDL-S1P under physical condition .Overexpression of PLTP decreases the HDL-S1P but increases LDL-S1P.The mechanism might be related to the capability of PLTP on trans-ferring S1P from erythrocyte to lipoprotein.