成年金黄地鼠大脑运动皮质神经元轴突的再生

THE AXONAL REGENERATION OF NEURONS IN THE MOTOR CORTEX OF ADULT HAMSTERS

在用ＨＲＰ逆行追踪法确定金黄地鼠大脑运动皮质的准确位置后，将截取的三组实验动物的自体坐骨神经分别插入之。存活８周后，在坐骨神经移植段的远端，注射２０％ＨＲＰ溶被１μｌ，做全脑及脊髓颈段连续冰冻切片，观察ＨＲＰ逆行标记的运动皮质锥体细胞。结果发现：在移植的正常坐骨神经段的诱导下，运动皮质神经元的受损轴突可以再生并长入到该移植段内（ｎ＝１２，平均＝９．７５），用预先渍变法未能导致运动皮质轴突再生神经元数目的增加（ｎ＝９，平均＝７．５），而经冻化处理后的移植神经则未能诱导出运动皮质神经元的轴奕再生。本文结果证明，周围神经移植法可诱导成年金黄地鼠运动皮质神经元的轴突再生，雪旺氏细胞的存在及其功能活动与锥体神经元轴突再生密切相关。

A segment of autologous sciatic nerve was transplanted into the motor cortex which was verified by retrograde labelling.Eight weeks after the implantation the presence of regenerated motor neurons was visualized by HRP histochemistry following the injection of the tracer into the distal end of the sciatic nerve graft. Labelled pyramidal neurons were found in the motor cortex suggesting that these neurons had sent their axons into the graft(n=12. mean=9.75). Implantation of the preconditional treatment of sciatic nerves which had been crushed a week prior to transplantation did not enhance the regeneration of pyramidal neurons in the motor cortex (n=9, mean=7.56). Furthermore. implantation of the sciatic nerve which was subjected to freezeand-thaw treatment was unable to induce regeneration of neurons in the cortex. the present study suggests that the peripheral nerve graft can induce regeneration of motor neurons in the cortex in hamsters and that the axonal regeneration of the CNS neurons may be related to the activity of the Schwann cells present in the peripheral nerve graft.