偏侧帕金森病样大鼠脑内微囊化牛嗜铬细胞移植实验

Cerebral transplant experiment of microencapsulated bovine chromaffin cells in hemiparkinsonian rats

目的:观察偏侧帕金森病样大鼠微囊化牛嗜铬细胞脑移植后多巴胺及其代谢产物含量的变化,探讨大鼠异常旋转行为改善的可能途径。方法:实验于1999-01／12在解放军总医院老年医学研究所完成。选择 6-羟基多巴立体定向损毁右侧黑质诱发的偏侧帕金森病样雌性SD大鼠30只,随机分为2组,微囊组20只,对照组10只。微囊组大鼠水合氯醛麻醉后于右侧纹状体立体定向植入约200个以海藻酸钠-多聚赖氨酸-海藻酸钠为材料含牛嗜铬细胞的微胶囊,对照组大鼠未做脑内移植手术。观察移植术前后阿朴吗啡(0．5 mg／kg)诱发的大鼠旋转行为。利用微透析技术采取帕金森病样大鼠脑纹状体区细胞外微透析液,用高效液相电化学层析法测定对照组大鼠在6-羟基多巴损毁右侧脑黑质后 16周时及两组大鼠在牛嗜铬细胞移植后12周时脑纹状体区细胞外液中单胺类物质含量的变化。结果:纳入偏侧帕金森病样大鼠30只,实验过程中微囊组麻醉意外、脑出血、肢体癫痫样抽搐死亡4只,对照组脑出血、不明原因死亡2 只。进入结果分析微囊组和对照维分别为16和8只大鼠。①微囊组移植后1周开始阿朴吗啡诱发的异常旋转次数明显减少,作用持续6个月以上(F=37．89,P<0．01)。②对照组帕金森病样大鼠右侧脑黑质损毁后16周时右侧脑纹状体区细胞外液中3,4-二羟基苯乙酸和高香草酸水平较左侧明显降低(t=7．012,4．394,P<0．01),右侧脑上述物质含量仅为左侧脑的8％和12％。③移植后12周,微囊组帕金森病样大鼠右侧脑纹状体区细胞外液中3,4-二羟基苯乙酸、高香草酸和5-羟基吲哚乙酸水平较对照组显著升高(t=4．273,4.402,6．445,P<0．01),分别提高了 3．1,5.3和2．7倍。结论:帕金森病样大鼠黑质损毁侧纹状体区多巴胺类物质含量明显降低, 移植微囊化牛嗜铬细胞后含量升高,使帕金森病样大鼠的运动功能障碍明显改善。

AIM： To observe the changes of contents of dopamine and its metabolite after cerebral transplant of microeneapsulated bovine chromaffin cell in hemiparkinsonian rats, and study the possible way of improving the special rotating behavior of rats. METHODS： The experiment was conducted at the Institute of Geriatric Medicine, General Hospital of Chinese PLA from January to December 1999. Thirty SD female rats with hemiparkinsonian due to lesioned substantia nigra side by stereo orientating 6-hydroxydopa were selected, and assigned randomly into 2 groups： microcapsule group with 20 rats and control group with 10 rats. About 200 micro-capsules containing bovine chromaffin cell, which were mainly composed of alginic acid natriummultiple poly-lysine- alginic acid natrium, were grafted into the striatum at the right side after chloral hydrate anesthesia in rats of microcapsule group. The rats in the control group were not treated with transplant operation in brain. The rotating behavior of rats induced by apomorphine （0.5 mg/kg） was observed before and after the transplantation. The micro-dialysate in corpus striatum outside cells in hemiparkinsonian rats was gained with micro-dialysate technology. The changes of content of monoamines substance of the extracellular fluid in cerebral corpus striatum region at the 16^th week after the lesioned substantia nigra side by 6-hydroxydopa in the control group and at the 12^nd week after the transplantation of bovine chromaffin cell in rats of the two groups were detected with high performance liquid chromatography （HPLC）. RESULTS： Among the included 30 hemiparkinsonian rats, four rats died in the microcapsule group during experiment, because of anesthesia accident, cerebral hemorrhage and limb epilepsy spasm, and two died in the control group, because of cerebral hemorrhage and unknown reason, therefore, 16 rats and 8 rats in the microcapsule group and control group, respectively were involved in the result analysis. ① After transplanting for 1 week, the number of special rotating due to apomorphine decreased significantly, and the effect lasted over 6 months （F=37.89,P 〈 0.01 ）. ②The levels of 3, 4-di-hydroxybenzene acetic acid and homovanillic acid of the extracellular fluid in corpus striatum region at the 16^th week after the lesion of substantia nigra at the right side in hemiparkinsonian rats in the control group decreased significantly than those in the left side （t=7.012,4.394,P 〈 0.01）. The content of the upmentioned substance at the right side brain was only 8% and 12% of the left brain. ③The levels of 3, 4-di-hydroxybenzene acetic acid, homovanillic acid and 5-hydroxy indoleacetic acid of the extracellular fluid in corpus striatum region at the right side in hemiparkinsonian rats in the microcapsule group increased significantly as compared with the control group （t=4.273,4.402,6.445,P 〈 0.01 ）, increased by 3.1,5.3 and 2.7 times after transplant for 12 weeks. CONCLUSION： The contents of dopamine and its metabolites in the striatum of lesioned substantia nigra side in hemiparkinsonian rats decreased markedly, and increased after transplantation of microencapsulated bovine chromaffin cells, which can significantly ameliorate the motor dys-function in hemiparkinsonian rats.