Lipid domains in plasma membranes from rat liver.
Lipid domains in plasma membranes from rat liver.
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大鼠肝脏质膜中的脂质结构域。
DOI：
10.1111/j.1432-1033.1983.tb07391.x
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Schroeder,F
中科院分区：
文献类型：
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作者：
Schroeder,F
分别以荧光脂肪酸-对羟基苯甲酸和顺式-对羟基苯甲酸作为固体膜和液膜区的探针分子，研究了大鼠肝细胞质膜中液体和固体脂质结构域的存在。荧光探针1，6-二苯基-1，3，5-己三烯表明，在18℃和30℃之间，肝细胞质膜发生了相变。在中等温度下，顺-羟基苯甲酸几乎均匀地分配到液体和固体脂类区域，检测到两个脂类结构域：24℃时，流体和固体类脂域的摩尔分数分别为0.32和0.68，而顺式-羟基苯甲酸的摩尔分数分别为0.34和0.66。其解离常数为7.0±0.7μM，膜-水脂分配系数为4.0±0.6×10 6，结合比为83：17。膜的亲和力比反式-肝素酸低两倍。反式-羟基苯甲酸优先分配为固体脂，Kps/f=3.30，而反式-羟基苯甲酸平均分配于液固两相，Kps/f=0.92。因此，这些数据证明了大鼠肝脏质膜中流体和固体结构域的共存。
The existence of fluid and solid lipid domains in isolated rat‐liver plasma membranes was evaluated using the fluorescent fatty acidstrans‐parinaric andcis‐parinaric acid as probe molecules for solid and fluid membrane areas, respectively. The fluorescence probe 1,6‐diphenyl‐1,3,5‐hexatriene indicated that a phase transition was present in the liver plasma membrane between 18°C and 30°C. At intermediate temperatures,cis‐parinaric acid, which partitioned approximately equally into fluid and solid lipid areas, detected two lipid domains: the mole fractions of fluid and solid lipid domains at 24°C were 0.32 and 0.68 while the mole fractions ofcis‐parinaric acid in each domain were 0.34 and 0.66, respectively. The dissociation constant, aqueous to membrane lipid partition coefficient, and bound to free ratio fortrans‐parinaric acid were 7.0 ± 0.7 μM, 4.0 ± 0.6 × 106, and 83:17, respectively. The affinity of the membrane forcis‐parinaric acid was twofold lower than fortrans‐parinaric acid. Thetrans‐parinaric acid partitioned preferentially into solid lipid.Kps/f= 3.30, while thecis‐parinaric acid partitioned equally between fluid and solid phasesKps/f= 0.92. Thus, the data demonstrate the coexistence of fluid and solid domains in rat liver plasma membranes.