冰片对中枢及周围神经髓鞘的影响

Effect of borneol on myelin of the central and peripheral nervous systems

目的探讨冰片对大鼠中枢及周围神经髓鞘的影响。方法SD大鼠根据灌服冰片石蜡油溶液的剂量不同分为低剂量（10mL／kg及高剂量（13mL／kg）2组，每组18只。另设对照组18只．灌服10mL／kg石蜡油溶液。3组大鼠灌服冰片或石蜡油溶液后24h、48h及72h取血并处死取脑、坐骨神经，进行血清髓鞘碱性蛋白（MBP）检测及透射电镜观察。结果3个观测时间点中，高、低剂量组大鼠MBP含量明显升高，与对照组比较差异有统计学意义（P〈0．05），但高、低剂量组之间差异无统计学意义（P〉0．05）。灌服冰片后24hMBP含量最高，随时间延长递减，各时间点之间比较差异有统计学意义（P〈0．05）。电子显微镜观察大鼠灌服冰片后各时间点均可见中枢神经髓鞘异常，出现外形不规则，板层之间裂开，宽窄不均，纤维缠结现象，以24h改变最明显，随时间延长异常减轻：坐骨神经髓鞘仅在灌服冰片后24h髓鞘数量出现明显减少，其余未见异常。结论冰片可引起大鼠中枢及周围神经髓鞘出现一定程度的异常。

Objective To study the effect of borneol on myelin of the central and peripheral nervous systems. Methods The rats were divided randomly into low-dose borneol treatment group （10 mL/kg, n=18） and high-dose borneol treatment group （13 mL/kg, n=18）. Controls （n=18） were chosen and treated with 10 mL/kg paroline. Rats were sacrificed 24, 48 and 72 h after the treatment, and the blood, brain and sciatic nerves of these rats were prepared, respectively; the level of serum myelin basic protein （MBP） was detected and the morphological structure of myelin was observed with transmission electron microscope. Results The content of serum MBP in the 2 treatment groups was advanced markedly as compared with that in the control group 24, 48 and 72 h after the treatment （P〈0.05）; however, no significant difference was noted between the 2 treatment groups （P〉0.05）. The content of serum MBP was the highest 24 h after the treatment, gradually decreased following the prolongation of time; significant difference was noted between each 2 time points （P〈0.05）. Transmission electron microscope indicated abnormality in myelin of the central nerves at all time points, showing inordinate shape, rupture between layers and tangle among fibers; the abnormality was the most obvious 24 h after the treatment, gradually abatement following the prolongation of time; decreased myelin in the sciatic nerves was showed only at 24 h after the treatment, while normal at other time points. Conclusion A certain degree of abnormality of myelin of the central and peripheral nervous systems in rats can be caused by borneol.