胚胎脊髓移植在恢复损伤脊髓传导功能中的作用

Effects of transplanting embryonic spinal cord on the restoration of injured spinal cord conduction

目的：探讨胚胎脊髓移植在恢复损伤脊髓传导功能中的作用。方法：将Ｅ１４胚胎脊髓植入成鼠损伤脊髓后３０、４５、６０天时，用单位放电记录技术观察了正常脊髓神经元和移植物神经元的自发放电活动，及其对刺激坐骨神经、红核和同时刺激的反应。结果：正常脊髓神经元的自发单位放电多是一个低频的单发脉冲活动。无论选择那种刺激方式，都可见兴奋、抑制和无反应三种反应。术后３０天时，胚胎神经元的自发单位放电以高频电脉冲活动为主，簇状放电所占比例较大，对刺激有反应的放电单位数也较少；随着动物存活时间的延长，这些单位放电的情况逐渐向着低频、单脉冲以及高反应率的方向发展。至术后６０天时，胚胎神经元单位放电的频率、形式以及对刺激的反应情况都变得和正常神经元的相似。结论：胚胎神经元移植后经历了一个逐渐发育分化过程，在这个过程中它们有可能逐渐和宿主神经元形成了功能性突触连接。

Objective: To study the effect of transplanting embryonic spinal cord on the restoration of injured spinal cord conduction. Methods:At day 30, 45, and 60 after embryonic spinal cord was transplanted into injured spinal cord of adult rats, autonomous discharge of the normal spinal cord neurons, embrynonic neurons, and their response to stimulating sciatic nerve, red nucleus and both were studied by exracellular potential recording. Results: Most autonomous discharge of the normal spinal cord neurons was regularly a single pulse with low frequency. No matter what kind of stimulation was given, they could respond with exciting, inhibiting or no response. At day 30 after operation, the neuronal discharge recorded in the graft acted mainly with a higher frequency electric pulse and higher ratio of burst discharge, and reacted with a lower responding number; afterwards conditions of the discharge developed towards lower frequency, single pulse and higher responding number. At the day 60 after transplantation, frequency, shap and resonding form of the discharge became similar to that of normal neurons. Conclusion: Embryonic neurons experience a growing and differentiating process after transplantation, and following it, functional synaptic connection between the graft and the host could frmed gradually.