冷冻预处理温度对SD大鼠周围神经超微结构的影响

Effect of Preliminary Temperature Management before Frozen on the Ultrastructure of Peripheral Nerve Tissue of SD Rat

目的 探讨不同冷冻预处理温度对周围神经超微结构的影响。 方法 以 15 %二甲基亚砜 (DMSO)为低温保护剂 ,采用两步冷冻步骤对 SD大鼠坐骨神经进行 - 4 5 ,- 5 0 ,- 5 5 ,- 6 0 ,- 6 5和 - 70℃冷冻预处理 ,- 196℃液氮保存 1周 ,复温后光镜和透射电镜观察。 结果 - 5 0℃冷冻预处理和液氮保存的的大鼠坐骨神经 ,超微结构保持良好。其余各温度组的神经呈髓鞘增厚、疏松 ,脱髓鞘、髓鞘断裂 ,轴索萎缩 ,局部裸露 ,雪旺细胞肿胀、坏死等轻重不同的冷冻损伤表现。 结论 周围神经冷冻预处理温度在 - 5 0～ - 5 5℃之间 ,- 5 0℃是其最佳温度值。

Objective\ To investigate the effect of preliminary temperature management before forzen on the ultrastructure of peripheral nerve of SD rat.\ Methods\ Two steps were adopted, first step the samples were treated with frozen protection reagent(15% DMSO) and there were frozen at -45, \{-50\}, -55, -60, -65 and -70 ℃ respectively before samples were stored at -196 ℃ liquid nitrogen for one week.\ The cell morphological changes were studied by using light mioroscopy and transmisson electron microscopy after rewarming.\ Results\ At the pretreatment temperature of -50 ℃ and after that samples were stored at -196 ℃ liquid nitrogen of sciatic nerve of SD rat, the ultrastructure of the nerve were well preserved.\ However other group, the myelin sheath thickening, rarefaction, myelinoclysis atrophy in the axons, edema or necrosis of Schwanns cells.\ Conclusion\ The preliminary temperature at \{-50 ℃\} before frozen peripheral nerve may be the optimal preliminary temperature.