Effects of sterols on permeability and phase transitions of bilayers from phosphatidylcholines lacking acyl groups.
Effects of sterols on permeability and phase transitions of bilayers from phosphatidylcholines lacking acyl groups.
复制标题
甾醇对缺乏酰基的磷脂酰胆碱双层的渗透性和相变的影响。
DOI：
10.1021/bi00513a013
复制
发表时间：
1981
期刊：
影响因子：
2.9
通讯作者：
Rosenthal,AF
中科院分区：
文献类型：
--
作者：
Bittman,R;Clejan,S;Jain,MK;Deroo,PW;Rosenthal,AF
Robert Bittman,* Sanda Clejan, Mahendra K. Jain, Paul W. Deroo和Arthur F. Rosenthal摘要：用合成的缺乏酰基的磷脂酰胆碱制备了超声囊泡。所使用的磷脂是含有1,2 -二十烷基、1,2 -二十六烷基、lc ‘ í-9’-十八烷基和2-六烷基链的二醚磷脂酰胆碱和烷基类似物，如（2-十八烷基）磷酸胆碱，它没有二酰基甘油或甘油二醚部分。在高于脂质相变的温度下，胆固醇和麦角甾醇降低了由valinomycin介导的86Rb+、由A23187介导的45Ca2+和水溶性荧光探针car- boxy荧光素的外排速率。25摩尔%的胆固醇掺入对囊泡的渗透性基本上没有影响。由于这些甾醇对由二醚磷脂酰胆碱制备的囊泡的渗透性的影响与由相应的二酯制备的囊泡的渗透性非常相似，因此可以得出结论，PC与甾醇相互作用的发生不需要PC的羰基氧；因此,从
Robert Bittman,* Sanda Clejan, Mahendra K. Jain, Paul W. Deroo, and Arthur F. Rosenthal abstract: Sonicated vesicles were prepared from synthetic phosphatidylcholines lacking acyl groups. The phospholipids used were diether phosphatidylcholines bearing 1, 2-ditetradecyl, 1, 2-dihexadecyl, and lc¡ í-9'-octadecenyl and 2-hexa-decyl chains and alkyl analogues such as (2-octadecyleicosyl) phosphorylcholine, which has no diacylglycerol or glycerol diether moiety. At temperatures above the lipid phase transition, cholesterol and ergosterolreduced the efflux rates of 86Rb+ mediated by valinomycin, of 45Ca2+ mediated by A23187, and of the water-soluble fluorescence probe, car-boxyfluorescein. Incorporation of epicholesterol at 25 mol% had essentially no effect on the permeability of the vesicles. Since the effects of these sterols on the permeability of vesicles prepared from dietherphosphatidylcholines were very similar to those found with vesicles from thecorresponding diesters, it was concluded that there is no requirement for the carbonyl oxygens of PC for PC-sterol interaction tooccur; thus, from