O'Neill C, Williams D C
Department of Biochemistry, Trinity College, Dublin, Ireland.
Neurochem Res. 1988 Sep;13(9):871-7. doi: 10.1007/BF00970756.
Bovine brain synaptic membranes which were frozen and then extensively washed showed low affinity [3H]muscimol binding. These membranes contained GABA and calmodulin, apparently tightly bound within the membrane fraction. Membranes which were additionally treated with the detergent Triton X-100 showed high affinity [3H]muscimol binding. These membranes did not appear to contain GABA or calmodulin. Transmission electron microscopy studies demonstrated that the washed membrane fraction contained many synaptosomal and vesicular structures. Triton treatment led to the extensive rupture of these structures. These studies explain the well-reported findings of tightly bound GABA and calmodulin in brain membrane fractions, as being due to the entrapment of these compounds inside sealed membrane-bound structures which are still present after a freeze-thaw and extensive wash treatment, their complete removal requiring Triton-treatment to rupture the vesicles.
冷冻后经大量洗涤的牛脑突触膜显示出低亲和力的[³H]蝇蕈醇结合。这些膜含有γ-氨基丁酸（GABA）和钙调蛋白，显然紧密结合在膜组分中。另外用去污剂曲拉通X-100处理的膜显示出高亲和力的[³H]蝇蕈醇结合。这些膜似乎不含GABA或钙调蛋白。透射电子显微镜研究表明，洗涤后的膜组分含有许多突触体和囊泡结构。曲拉通处理导致这些结构大量破裂。这些研究解释了在脑膜组分中GABA和钙调蛋白紧密结合这一广泛报道的发现，是由于这些化合物被困在冻融和大量洗涤处理后仍存在的密封膜结合结构内，要完全去除它们需要曲拉通处理以使囊泡破裂。
