Ansari K A, Rand A, Hendrickson H, Bentley M D
J Neuropathol Exp Neurol. 1976 Mar;35(2):180-90. doi: 10.1097/00005072-197603000-00005.
Normal human frontal lobe white matter obtained at autopsy was used to determine the extent of in situ post-mortem degradation of myelin basic protein (BP). Effects of the following two factors were studied: 1) time interval between death and autopsy, and 2) freezing and thawing the tissue. Quantitative extraction of BP from the autopsy material showed only minimal loss of BP that could be attributed to the time interval between death and autopsy (up to 48 h). The purified BP from these samples was electrophoresed on acrylamide gels at pH 4.3 and it was found that the electrophoretic patterns were comparable to zero hour bovine BP samples. The BP obtained from the autopsy samples was found to be encephalitogenic in guinea pigs. When tested against rabbit anti-human-BP serum, the purified BP preparations gave a single arc in immunoprecipitin test. BP extracted and purified from tissue that was frozen once and processed before it could thaw showed yields, encephalitogenic activity and acrylamide disc gel electrophoretic patterns that were similar to those of BP from tissue that was never frozen. However, frozen tissue that was thawed and then incubated for 8 h at room temperature before processing yielded only 13-25% of the total extractable protein. This BP also was encephalitogenic and showed acrylamide banding pattern that was similar to BP from tissue that was never frozen. Samples of white matter were examined by electron microscope. Unfrozen autopsy material showed some separation of myelin lamellae. Myelin in sections of frozen and thawed white matter showed separation as well as disruption of the lamellae. Samples that were frozen, thawed and then incubated at room temperature for 8 h showed sporadic loss of dense line material in addition to lamellar separation and disruption. The results a) show that BP is quite resistant to autolytic changes and b) are consistent with the location of BP along the cytoplasmic surface of the myelin membrane.
取自尸检的正常人额叶白质被用于确定髓鞘碱性蛋白（BP）在死后原位降解的程度。研究了以下两个因素的影响：1）死亡与尸检之间的时间间隔，以及2）组织的冻融。从尸检材料中定量提取BP，结果表明，BP的损失极小，这可归因于死亡与尸检之间的时间间隔（长达48小时）。将这些样品中纯化的BP在pH 4.3的丙烯酰胺凝胶上进行电泳，发现其电泳图谱与零时牛BP样品相当。从尸检样品中获得的BP在豚鼠中具有致脑炎性。当用兔抗人BP血清进行检测时，纯化的BP制剂在免疫沉淀试验中呈现单一条带。从冷冻一次且在解冻前进行处理的组织中提取和纯化的BP，其产量、致脑炎性活性和丙烯酰胺圆盘凝胶电泳图谱与从未冷冻过的组织中的BP相似。然而，解冻后在室温下孵育8小时再进行处理的冷冻组织，其总可提取蛋白仅产生13 - 25%。这种BP也具有致脑炎性，并且其丙烯酰胺条带图谱与从未冷冻过的组织中的BP相似。用电子显微镜检查白质样品。未冷冻的尸检材料显示髓鞘板层有一些分离。冷冻和解冻后的白质切片中的髓鞘显示出板层的分离以及破坏。冷冻、解冻后在室温下孵育8小时的样品，除了板层分离和破坏外，还出现了致密线物质的散在丢失。结果a）表明BP对自溶变化具有相当的抗性，并且b）与BP沿髓鞘膜细胞质表面的位置一致。
