Onji T, Liu M S
Circ Shock. 1981;8(4):403-10.
The effect of E coli endotoxin on the leakage of 14C-sucrose from phosphatidylcholine liposomes in the absence or presence of Ca2+ was studied. Endotoxin decreased the leakage from liposomes from 27% to 4% in 5 hr when Ca2+ (1 mM) was incorporated into liposomes during sonication. The effect of endotoxin on the leakiness of liposomes was concentration dependent. Ca2+ alone increased the leakage of 14C-sucrose from liposomes. Mg2+ at concentrations higher than 5 mM exhibited an effect similar to that of Ca2+. These findings suggest that endotoxin increases the molecular packing of phosphatidylcholine bilayers in the presence of Ca2+ or Mg2+. A change in the physical state of membrane lipid bilayers induced by endotoxin may affect the function of biological membranes.
研究了大肠杆菌内毒素在不存在或存在Ca2+的情况下对14C-蔗糖从磷脂酰胆碱脂质体泄漏的影响。当在超声处理过程中将Ca2+（1 mM）掺入脂质体时，内毒素在5小时内将脂质体的泄漏率从27%降低到4%。内毒素对脂质体渗漏的影响呈浓度依赖性。单独的Ca2+会增加14C-蔗糖从脂质体的泄漏。浓度高于5 mM的Mg2+表现出与Ca2+类似的作用。这些发现表明，内毒素在存在Ca2+或Mg2+的情况下会增加磷脂酰胆碱双层的分子堆积。内毒素诱导的膜脂质双层物理状态的变化可能会影响生物膜的功能。
