大鼠海马内神经胶质细胞放射反应性的研究

Radioreponse of neurogliocytes in the hippocampus of rat brain.

目的 通过对大鼠大脑受照射后海马中各类神经胶质细胞数量变化的观察 ,研究胶质细胞在放射性脑损伤发病原理中所起的作用。方法 在大鼠一侧大脑半球单次 10、2 0、30Gy照射后1周、1个月和 3个月时 ,用免疫组织化学染色法分别标记星形胶质细胞、少突胶质细胞和小胶质细胞 ,观察海马区域中各种胶质细胞数量的变化 ,并分析照射剂量、照射后时间对其的影响。结果 随着剂量的增加和观察时间的延长 ,特别是 30Gy照射后 3个月时 ,受照射侧大脑海马中有星形胶质细胞和小胶质细胞数的显著增加 ,同时有少突胶质细胞数量的减少。结论 在大脑受电离辐射后早期 ,脑组织内各种胶质细胞可出现一系列的改变 。

Objective To identify the radiation effect on different kinds of neurogliocytes in the hippocampus of rat brain and its dose, time relationship.Methods The brain sections were immunohistochemically stained separately with glial fibrillary acidic protein (GFAP), 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and CD11b(OX-42), to label the astrocytes, oligodendrocytes and microglial cells respectively. The number of GFAP, CNPase, and OX-42 positive cells in hippocampus were recorded and the data were analyzed by the Student's t test. Results By comparison with the unirradiated hemibrain, the relative number of GFAP and OX-42 positive cells increased in the hippocampus and the CNPase positive cells decreased in the irradiat hemibrain. The degree of change was both dose and time related and it was most significant at three months after 30?Gy irradiation. Conclusions The quantitative variation of different neurogliocytes in the hippocampus suggests that in addition to the decreasing traditional oligodendrocyte lineage, other increasing phenotypes, such as the astrocytes and microglial cells, as well as cellular interactions may also be involved in the pathogenetic process of brain radiation injury in the early stage.