碘125间质内照射治疗大鼠脑内胶质瘤的实验研究

Experimental study of Iodine-125 brachytherapy to brain glioma in rats

目的通过建立大鼠脑内C6胶质瘤动物模型,研究碘125聚胺酯放射材料间质内照射对恶性胶质瘤的治疗作用。方法Wistar大鼠30只,体外培养大鼠C6胶质瘤细胞,采用立体定向方法接种于大鼠脑内右尾状核区建立肿瘤模型,而后分为对照组15只,治疗组15只。1周后行MRI检查观察肿瘤生长情况,对照组在原脑内靶点注入无碘125材料,治疗组注入碘125聚胺酯放射材料,平均放射活度37 mBq。分别于2、3、4周通过MRI检查测量两组肿瘤直径,最后处死行病理组织学检查。结果C6细胞接种后1周,大鼠脑内均可见肿瘤形成。对照组与治疗组肿瘤直径增长速度明显不同,4周后治疗组明显小于对照组(P<0.001),病理学检查见治疗组肿瘤细胞坏死及内部结构损伤。结论碘125聚胺酯放射材料可通过间质内照射对大鼠脑内C6胶质瘤细胞产生杀伤作用,抑制肿瘤生长,有望用于人脑胶质瘤的治疗。

Objective To investigate the therapeutical effect of Iodine-125 brachytherapy to malignant glioma based on establishment of C6 brain glioma model in rats. Methods Test animals were 30 Wistar rats. C6 glioma cells were cultured in vitro and injected into the right eaudate nucleus of rats＇ brains to establish a rat brain tumor model by directional implantation method. The rats were randomly divided into 2 groups： experimental group（n = 15）, control group（n = 15）. Rats＇ brains MRI were detected after 1 week.Control group were implanted non-radio materal into brain caudate nucleus target, experimental group were implanted Iodine-125 polyamine-ester material into brain caudate nucleus target, median radio activity 37 mBq. Correspondingly in the 2,3,4week, rats＇ brains MRI of two groups were detected to measure tumor diameter and tumor histopathologic examination were performed in the end. Results Tumor appeared in rats＇ brains caudate nucleus about 1 week after C6 cells were injected into them. Tumor diameter growth was significantly different between two groups, experimental group tumors were more smaller than control group after 4 weeks （P 〈 0. 001）. The cellular necrosis and-damage of internal structure were observed in histopathologic examination. Conclusion Rat C6 glioma cells can be killed and wounded by braehytherapy of Iodine-125 polyamine-ester materal, tumor growth is obviously inhibited, Iodine-125 polyamine-ester materal is expected for the treatment of human glioma.