周围神经损伤后神经组织中Par-3蛋白表达和分布的变化

目的观察极性蛋白Par-3在损伤后神经组织中的表达和分布,探讨Par-3蛋白在周围神经损伤后髓鞘再生中的作用。方法 32只Sprague Dawley大鼠随机分为正常对照组、损伤组(坐骨神经损伤后第1、2、4、8周)。制备坐骨神经挤压伤模型,分别于损伤后各时间点,采用免疫组织化学法检测坐骨神经损伤远端Par-3蛋白的表达和分布。结果正常大鼠坐骨神经组织中即存在Par-3蛋白,但表达量少,且仅分布于Schwann细胞核内。坐骨神经损伤后,Par-3蛋白的表达和分布发生变化。损伤后1周,Par-3蛋白表达开始升高,Par-3散在分布于Schwann细胞核和细胞浆内。损伤后2周,神经组织中的Par-3蛋白达峰值,在Schwann细胞浆内呈不对称性分布似包绕轴突,呈新月形或C形。损伤后4周和8周,Par-3蛋白表达显著降低,神经组织中Par-3蛋白主要分布于Schwann细胞核内,胞浆内很少。结果 极性蛋白Par-3可能参与周围神经损伤后Schwann细胞的髓鞘再生。

EXPRESSION AND DISTRIBUTION OF PAR-3 PROTEIN IN PERIPHERAL NERVE TISSUES AFTER INJURY

Objective To observe the expression and distribution of the polarity protein Par-3 in nerve tissues after peripheral nerve injury,and to investigate the role of Par-3 protein in Schwann cell myelination.Methods 32 Sprague-Dawley rats were randomly divided into a control group and experimental groups,the latter was subdivided into 1,2,4 and 8-week groups after sciatic nerve injury.The expression and distribution of Par-3 in sciatic nerve tissues distal to the injury site was examined by using immunohistochemistry.Results Par-3 protein existed in the normal sciatic nerve tissues,but in small quantities,and only localized in Schwann cell nucleus.After sciatic nerve injury,the expression and distribution of Par-3 protein changed.At 1 week post injury,Par-3 protein in Schwann cells began to increase,scattered in both the nucleus and the cytoplasm within Schwann cells.At 2 weeks post injury,Par-3 protein reached a peak expression and was asymmetrically distributed in the cytoplasm within Schwann cells surrounding axons,exhibiting a half-moon or C-shape.At 4 and 8 weeks post injury,the expression of Par-3 protein was markedly reduced,mainly found in Schwann cell nucleus,but rarely in the cytoplasm.Conclusion Our findings suggest that the polarity protein Par-3 may play a role in Schwann cell remyelination after peripheral nerve injury.