Mazzanti L, Curatola G, Zolese G, Bertoli E, Lenaz G
J Bioenerg Biomembr. 1979 Apr;11(1-2):17-32. doi: 10.1007/BF00743158.
We have studied the effect of general anesthetics on the mobility of two stearic acid spin labels (5-doxyl stearic acid and 16-doxyl stearic acid) in bovine heart mitochondria and in phospholipid vesicles made from either mitochondrial lipids or commercial soybean phospholipids. The general anesthetics used include nonpolar compounds (alcohols, halothane, pentane, diethyl ether, chloroform) and the amphiphatic compound, ketamine. All anesthetics tested increase the mobility of the spin labels in phospholipid vesicles to a limited extent up to a concentration where the ESR spectra become those of free spin labels. On the other hand, anesthetics have a pronounced effect on mitochondrial membranes at concentrations as low as those known to produce general anesthesia; the effect is lower near the bilayer surface (5-doxyl stearic acid) and very strong in the bilayer core (16-doxyl stearic acid). The effects of anesthetics are mimicked by the detergent, Triton X-100. We suggest that the discrepancy between the action of anesthetics in mobilizing the spin labels in lipid vesicles and in membranes results from labilization of lipid protein interactions.
我们研究了全身麻醉剂对牛心线粒体以及由线粒体脂质或市售大豆磷脂制成的磷脂囊泡中两种硬脂酸自旋标记物（5 - 脱氧硬脂酸和16 - 脱氧硬脂酸）流动性的影响。所使用的全身麻醉剂包括非极性化合物（醇类、氟烷、戊烷、乙醚、氯仿）和两性化合物氯胺酮。所有测试的麻醉剂在一定浓度范围内会有限地增加磷脂囊泡中自旋标记物的流动性，直至电子自旋共振（ESR）光谱变为自由自旋标记物的光谱。另一方面，麻醉剂在低至已知可产生全身麻醉的浓度时，就会对线粒体膜产生显著影响；这种影响在双层表面附近（5 - 脱氧硬脂酸）较小，而在双层核心（16 - 脱氧硬脂酸）非常强烈。麻醉剂的作用可被去污剂Triton X - 100模拟。我们认为，麻醉剂在脂质囊泡和膜中使自旋标记物移动的作用之间的差异是由脂质 - 蛋白质相互作用的不稳定引起的。
