钴60放射法制备免疫功能抑制大鼠模型

Animal model preparation for inhibit the immunologic function with radiotherapy in rats

目的通过系统的钴60放射计划,对大鼠免疫功能抑制的合适剂量进行评估,为干细胞移植研究提供合适的的动物模型。方法SD大鼠随机分为12.5Gy、10Gy、7.5Gy、5Gy4个剂量组,10只/组。计算放射后2个月的死亡率。检测白细胞数量,评价各剂量组动物的白细胞参考值范围。结合死亡率和白细胞参考值范围,确定合适的放射剂量。通过对外周血中性粒细胞(PMN)吞噬实验和外周血白细胞移行抑制实验(MIT),对细胞免疫功能进行检测。结果行12.5Gy照射的大鼠,3d内全部死亡;10Gy放射后的大鼠在1个月内全部死亡;7.5Gy照射的大鼠2个月内死亡1只;5Gy照射的大鼠没有死亡情况发生。设定95%作为可信区间,计算白细胞数量参考值范围(109个/L),未放疗组:16.978+1.96×6.46;5Gy放疗组:4.93+1.96×0.72;7.5Gy放疗组:2.313+1.96×0.782;10Gy放疗组:1.03+1.96×0.507。t检验表明,随着放疗剂量的增加,各实验组的白细胞数量显著减少。对于细胞免疫功能的检测,外周血中性粒细胞(PMN)吞噬实验结果表明,机体全身免疫功能降低;外周血白细胞移行抑制实验(MIT)表明,机体T细胞免疫功能降低。结论7.5Gy可以一定程度上抑制大鼠的免疫功能,为合适的放疗剂量。

Objective Through systematic radiotherapy, to evaluate the appropriate dose of radiotherapy in inhibiting the rat immunological function, and to offer the suitable use of reference in animal model preparation for the study on the organ transplantation. Methods Co 60 X ray machine SD rat, 4 dose groups as 12.5 Gy,10 Gy,7,5 Gy,5 Gy. 10 rat/group. During the operation of radiotherapy, the head of rat was out of the radiation region in order to avoid the hydrocephalus, The mortality within 2 months after radiotherapy was calculated. The amount of leukocyte was checked, to calculate the average value and the standard differentiation. The motarlity rate and the reference value limitations of amount of leukocyte were. wed determine the appropriate dose of radiotherapy. The PMN phagocytic rate and index of MTT were measured to check the immufunction. Results The rats receiving 12.5 Gy radiation died within 3 days, The rats receiving 10 Gy radiation died within one month. There was only one died among rats receiving 7.5 Gy radiation. No rat died under the 5 Gy radiation, As for the reference value limitations of the amount of leukocytes, 16.978 ＋ 1.96x6.46 for rats without radiotherapy, 4,93＋1.96x0,72 for rats with 5 Gy radiotherapy, 2.313＋1,96x0.782 for rats with 7,5 Gy radiotherapy, and 1,03＋1.96x0,507 for rats with 10 Gy radiotherapy. The cell amount of leukocytes decreased significantly with the increase of the doses of radioatherapy. The PMN phagocytic rat decreased significantly and index of MIT increased significantly in the 7.5 Gy radiotherapy group. Conclusion The radiation with 7.SGy could inhibit the rat immunologic function, and could be the appropriate dose of radiotherapy,