胚胎黑质植入震颤麻痹模型鼠脑内的研究

An study on the substantia nigra of embryo transplants into brain of rat model of paralysis agitans

采用 6 -羟基多巴胺 (6 - OHDA)分两点注入 SD鼠右侧中脑黑质内侧端 ,制成震颤麻痹模型 ,毁损后 6 - 8周 ,用胚龄 14- 16天同种胚鼠中脑黑质细胞悬液植入模型鼠尾壳核。实验分正常对照组 ,模型对照组 ,单纯胚中脑黑质移植组(MS组 ) ,含层粘蛋白 L am inin胚中脑黑质移植组 (L MS组 ) ,含雪旺氏细胞胚中脑黑质移植组 (SMS组 )。 MS组、L MS组及 SMS组于移植后 2～ 4个月分别测试旋转试验与模型组间均有显著差异。动物在存活 2～ 4个月测试后处死。脑切片观察发现 ,损伤侧中脑黑质 DA神经元 95 %以上死亡 ,移植组织位于尾壳核背侧并突入侧脑室 ,L MS组移植区 >SMS组移植区 >MS组移植区。三个移植区均见 TH、GABA免疫阳性细胞 ,其形态及大小与正常对照侧中脑黑质所见相似。L MS组与 SMS组多巴胺阳性细胞突起较 MS组多且长。本实验证明中脑黑质移植物 L aminin与雪旺氏细胞均能促进神经元突起生长。

Paralysis Agitans (PA)rat model was produced by injection of 6 hydroxydopamine (6 OHDA) into the right medial part of substantia nigra. 6～8 weeks post lesion, fetal (E 14～15) substantia nigra cell suspension was implanted into the caudate putamen (CP) and rats were devided into five groups; group I normal control rats (n=4), group Ⅱ model control rats (n=4),group Ⅲ simple transplanted with fetal substantia nigra cell suspension (n=6,MS group), group Ⅳ implanted with substantia nigra cell suspension containing laminin (n=6,LMS group). group Ⅴ grafted with substantia nigra cell suspension containing the cultured schwann cells(n=6, SMS group).2～4 months after grafting, the rotation tests was carried, the results showed that there were significant differences between grafted group and model control group at 3～4 months. After the behavioural test, the rat brain was investigated morphologically. About 95% DA neurons of the lesioned substantia nigra of fetal mesencephalon were died and the graft was located at the dorsal part of caudate putamen and projected into the lateral ventricle. The volume of the graft area of LMS group was larger than that of SMS group and the volume of the graft area of SMS group was larger than that of MS group. TH, GABA positive neurons were found in the graft area of the three grafted groups and their shape and size were similar to those of normal substantia nigra of fetal mesencephalon. The processes of DA positive neurons in the graft of LMS group and SMS group were more and longer than that in the graft of MS group. The results indicate that Laminin and cultured Schwann cells in the graft area of the substantia nigra of fetal mesencephalon may support the neuronal survival and growth in vivo.